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272 Cards in this Set
- Front
- Back
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Cellular mechanism of action of steroid/thyroid hormones
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1. Steroid binds to receptor located in cytoplasm or nucleus; 2. Translocation to nucleus, and transformation of receptor to expose DNA binding domain; 3. Binding to enhancer-like element on DNA effects transcription of genes (↑ or ↓)
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Why is the onset of action of steroid hormones delayed?
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need for transcription and protein synth delays onset of action of ssteroid hormones
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Name 6 steroid/thyroid hormones
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PET CAT: Progesterone, Estrogen, Testosterone, Cortisol, Aldosterone, Thyroxine/T3
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What is the result of ↑ levels of sex hormone-binding globulin (SHBG) on the levels of free testosterone?
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Lower free testosterone→ gynecomastia
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What is the result of ↓ levels of sex hormone-binding globulin (SHBG) on levels of free testosterone?
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Increased level of free testosterone→ hirstuism
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Name 5 functions of thyroid hormones
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1. Bone growth (synergism w/ GH); 2. CNS maturation; 3. β-adrenergic effects (↑CO, HR, SV, contractility); 4. ↑basal metabolic rate; 5. ↑glycogenolysis, gluconeogenesis, lipolysis
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What is the effect of liver failure on the amount of thyroxine-binding globulin (TBG)? How will the free T3/T4 be affected?
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Liver failure=↓TBG; ↑free T3/T4
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What is the effect of pregnancy on the amount of thyroxine-binding globulin (TBG)? How will the free T3/T4 be affected?
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Pregnancy=↑TBG (estrogen ↑TBG); ↓free T3/T4
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What is the major product of thyroid hormone synthesis, and what is it converted to in peripheral tissue?
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T4=major product, converted to T3 in peripheral tissue; T3 binds receptor with HIGHER affinity
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What stimulates thyroid hormone secretion (hypothal/pituitary axis)?
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TRH from hypothalamus stimulates TSH release from pituitary, which stimulates follicular cells of thyroid gland to secrete thyroid hormone.
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What acts as negative feedback on the hypothal/pituitary axis in thyroid hormone secretion?
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T3 acts on anterior pituitary to ↓sensitivity to TRH
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What are 2 types of tissue that are dependent on insulin for glucose uptake? What is the transporter?
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Skeletal muscle, adipose tissue; GLUT-4
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What are 2 types of tissue that take up glucose independent of insulin levels? What is the transporter?
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Brain and RBCs; GLUT-1
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What is the brain's energy source under normal conditions? (in the fed state)
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Glucose metabolism
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What is the brain's energy source during starvation?
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Ketone bodies
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Where is cortisol synthesized?
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Adrenal zona fasiculata
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Name 5 functions of cortisol
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1. Anti-inflammatory; 2. ↑gluconeogenesis, lipolysis, proteolysis; 3. ↓immune function; 4. maintains blood pressure; 5. ↓bone formation
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What stimulates cortisol secretion (hypothal/pituitary axis)?
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CRH from hypothalamus stimulates ACTH release from pituitary, which causes cortisol production in the adrenal zona fasiculata
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How is cortisol transported in the blood?
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Bound to corticosteroid-binding globulin (CBG)
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What hormone is involved in Cushing's Syndrome, and is it ↑ or ↓?
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↑ Cortisol
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Symptoms/Clinical features of Cushing's Syndrome
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Hypertension, Weight gain, Moon facies, Truncal obesity, Buffalo hump, Hyperglycemia (insulin resistance), thinning skin/striae, osteoporosis, amenorrhea, immune suppression
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What will be the results of the Dexamethasone suppression test in a healthy individual?
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↓ cortisol after a low dose
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In the Dexamethasone suppression test, what does ↑cortisol after a low dose/↓cortisol after a high dose indicate?
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ACTH-producing pituitary tumor
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In the Dexamethasone suppression test, what does ↑cortisol after a low dose/↑cortisol after a high dose indicate?
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Ectopic ACTH-producing tumor or a cortisol-producing tumor
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In Cushing's disease (primary pituitary adenoma), what will the levels of ACTH be?
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↑ACTH
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In primary adrenal hyperplasia/neoplasia, what will the levels of ACTH be?
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↓ACTH
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What is a common site of ectopic ACTH secretion? (a type of cancer)
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Small cell lung cancer
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In Cushing's syndrome, caused by chronic steroid use (iatrogenic), what will the levels of ACTH be?
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↓ACTH
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What is the cause of Primary Hyperaldosteronism?
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Aldosterone-secreting tumor
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What are the sx of Primary Hyperaldosteronism?
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Hypertension, Hypokalemia, Metabolic alkalosis, LOW plasma renin
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Name 5 causes of Secondary Hyperaldosteronism
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Renal artery stenosis, Chronic renal failure, CHF, Cirrhosis, Nephrotic syndrome
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How would renal artery stenosis cause Secondary Hyperaldosteronism?
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Kidney perceives low blood volume, which activates renin-angiotensin system→ increased aldosterone secretion & HIGH plasma renin levels
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Treatment for hyperaldosteronism?
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Spironolactone (K-sparing diuretic that is an aldosterone antagonist)
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What is Addison's Disease?
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Primary deficiency of aldosterone and cortisol d/t adrenal atrophy or destruction.
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Symptoms/Clinical features of Addison's Disease?
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Hypotension, skin hyperpigmentation, adrenal atrophy w/ absence of hormones from all 3 cortical divisions
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Acute adrenocortical insufficiency→ adrenal hemorrhage syndrome associated w/ meningococcal septicemia
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Waterhouse-Friderichsen syndrome
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What disease is characterized by postpartum hypopituitarism→ caused by infarction of the pituitary gland following severe bleeding and hypoperfusion during delivery?
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Sheehan's syndrome
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What are the sx of Sheehan's Syndrome?
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Fatigue, anorexia, poor lactation, loss of pubic and axillary hair
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What is the most common tumor of the adrenal medulla in adults?
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Pheochromocytoma (derived from chromaffin cells, which arise from neural crest)
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What is the most common tumor of the adrenal medulla in children?
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Neuroblastoma (can occur anywhere along the sympathetic chain)
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What 3 things are secreted by a pheochromocytoma?
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Epinephrine, Norepinephrine, Dopamine
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What drug can treat pheochromocytomas?
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Phenoxybenzamine: an irreversible α-antagonist
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What is the inheritance pattern of the Multiple Endocrine Neoplasia (MEN) syndromes?
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Autosomal dominant
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What 3 tumors are associated w/ MEN type I syndrome?
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pan-para-pit→ pancreas, parathyroid, and pituitary tumors {3P's}
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What 3 tumors are associated w/ MEN type II syndrome?
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Medullary carcinoma of the thyroid, Pheochromocytoma, Parathyroid tumor {2P's}
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What 3 tumors are associated w/ MEN type III (formerly MEN IIb) syndrome?
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Medullary carcinoma of the thyroid, Pheochromocytoma, Intestinal ganglioneuromatosis {1P}
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What gene are MEN II and MEN III associated with?
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ret gene
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Symptoms of hypothyroidism?
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Cold intolerance, hypoactivity, weight gain, fatigue, lethargy, ↓appetite, constipation, weakness, ↓reflexes, myxedema, dry cool skin, coarse brittle hair
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Symptoms of hyperthyroidism?
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Heat intolerance, hyperactivity, weight loss, chest pain/palpitations, arrhythmias, diarrhea, ↑reflexes, warm moist skin, fine hair
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Autoimmune hyperthyroidism d/t thyroid-stimulating/TSH-receptor Antibodies
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Graves' Disease
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What is Thyroid Storm?
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Underlying Graves' disease with a stress-induced catecholamine surge, leading to death by arrhythmia
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What are the TSH, total T4, free T4, and T3 uptake in hypothyroidism?
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↑TSH ↓total T4 ↓free T4 ↓T3 uptake
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What are the TSH, total T4, free T4, and T3 uptake in primary hyperthyroidism?
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↓TSH ↑total T4 ↑free T4 ↑T3 uptake
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Autoimmune disorder resulting in hypothyroidism
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Hashimoto's thyroiditis
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What Antibodies are associated w/ Hashimoto's Thyroiditis?
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Antimicrosomal and antithyroglobulin antibodies
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Self-limited hypothyroidism, often following a flu-like illness, with a very tender thyroid gland
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Subacute thyroiditis (de Quervain's)
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Most common type of thyroid cancer, with an excellent prognosis, ground-glass (Orphan Annie) nuclei, psammoma bodies
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Papillary carcinoma → increased risk w/ childhood irradiation
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Thyroid cancer with a good prognosis, and uniform follicles
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Follicular carcinoma
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Thyroid cancer originating from C cells that produces calcitonin, with sheets of cells in an amyloid stroma
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Medullary carcinoma → associated w/ MEN II and III
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Thyroid cancer seen in older pts, with a very poor prognosis
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Undifferentiated/anaplastic thyroid carcinoma
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Thyroid cancer associated with Hashimoto's thyroiditis
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Lymphoma
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Characteristics of Cretinism
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Child who is pot-bellied, pale, puffy-faced, w/ protruding umbilicus and protruberant tongue, severe mental retardation
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What is the cause of Endemic Cretinism? Sporadic?
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Endemic Cretinism→ occurs wherever endemic goiter is prevalent d/t lack of dietary iodine; Sporadic Cretinism→ d/t defect in T4 formation or developmental failure in thyroid formation
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Disease caused by excess GH in adults, characterized by large tongue, deep voice, large hands and feet, coarse facial features, impaired glucose tolerance
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Acromegaly
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Disease caused by excess GH in children
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Gigantism
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Pharmacological treatment for acromegaly
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Octreotide―somatostatin analog
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Most common cause of Primary Hyperparathyroidism
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Adenoma
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Symptoms of Primary Hyperparathyroidism
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Renal stones, painful bones, abdominal groans, psychic moans; weakness and constipation
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What are the levels of Ca, Phosphate, PTH, and Alkaline Phosphatase in primary hyperparathyroidism?
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↑ Ca ↓PO4 ↑PTH ↑ALP ↑cAMP in urine
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Most common cause of Secondary Hyperparathyroidism
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Chronic renal disease→ hypocalcemia causes secondary hyperplasia of parathyroid glands
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What are the levels of Ca, Phosphate, Alkaline Phosphatase, and PTH in secondary hyperparathyroidism?
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↓ Ca ↑PO4 ↑ALP ↑PTH
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What is Osteitis fibrosa cystica?
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cystic bone spaces, filled w/ brown fibrous tissue; associated with hyperparathyroidism
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What is Renal osteodystrophy associated with?
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Secondary hyperparathyroidism (d/t renal disease); ↑PTH + ↓ 1,25-OH vit D production leads to increased bone resorption
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What is Chvostek's sign? What is it associated with?
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Tapping facial nerve elicits contraction of facial muscles; Hypoparathyroidism
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What is Trousseau's sign? What is it associated with?
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Occlusion of the brachial artery w/ a BP cuff → carpal spasm; Hypoparathyroidism
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Autosomal dominant disorder associated w/ unresponsiveness of the kidney to PTH, hypocalcemia, shortened stature, shortened 4th/5th digits
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Pseudohypoparathyroidism
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Name 3 causes of hypoparathyroidism
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Surgical excision (thyroid surgery), autoimmune destruction, or DiGeorge syndrome
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What are Ca levels in hypoparathyroidism?
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↓Ca
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Name 11 causes of hypercalcemia
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CHIMPANZEES: Ca ingestion, Hyperparathyroidism, Hyperthyroidism, Iatrogenic (thiazides), Multiple myeloma, Paget's disease, Addison's disease, Neoplasms, Zollinger-Ellison syndrome, Excess vitamin-D, Excess vitamin A, Sarcoidosis
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What are the symptoms of a pituitary adenoma―prolactinoma?
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amenorrhea, galactorrhea, low libido, infertility, bitemporal hemianopia
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What drug can treat a prolactinoma?
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Bromocriptine→ dopamine agonist, will cause shrinkage b/c DA inhibits prolactin secretion
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What 2nd messenger is associated w/ the ACTH signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the ANP signaling pathway?
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cGMP
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What 2nd messenger is associated w/ the LH and FSH signaling pathways?
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cAMP
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What 2nd messenger is associated w/ the TSH signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the EDRF signaling pathway?
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cGMP
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What 2nd messenger is associated w/ the NO signaling pathway?
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cGMP
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What 2nd messenger is associated w/ the ADH (V2) signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the GnRH signaling pathway?
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IP3
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What 2nd messenger is associated w/ the TRH signaling pathway?
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IP3
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What 2nd messenger is associated w/ the hCG signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the MSH signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the GHRH signaling pathway?
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IP3
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What 2nd messenger is associated w/ the CRH signaling pathway?
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cAMP
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What is the Insulin receptor/signaling pathway coupled to?
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Tyrosine kinase
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What 2nd messenger is associated w/ the PTH signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the ADH (V1) signaling pathway?
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IP3
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What is the IFG-1 receptor/signaling pathway coupled to?
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Tyrosine kinase
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What 2nd messenger is associated w/ the Calcitonin signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the Glucagon signaling pathway?
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cAMP
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What 2nd messenger is associated w/ the Oxytocin signaling pathway?
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IP3
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What is the FGF receptor/signaling pathway coupled to?
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Tyrosine kinase
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A woman presents w/diffuse goite & hyperthyroidism. What are the expected values of TSH and thyroid hormones?
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Low TSH and high thyroid hormones
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48 y/o woman presents w/progressive lethargy and extreme cold sensitivity to cold Ts. What is the dx?
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Hypothyroidism
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Patient with elevated serum cortisol levels undergoes a dexamethasone suppression test. 1 mg of dexamethasone does not decrease cortisol levels, but 8 mg does. What is the dx?
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Pituitary Tumor
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50 y/o man complains of diarrhea. On PE, his face plethoric and a heart murmur is detected. What is the dx?
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Carcinoid Tumor
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Woman of short stature presents with shortened 4th & 5 th metacarpals. What endocrine disorder comes to mind?
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Albright's hereditary osteodytrophy/ pseudohypoparathyroidism
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Nondiabetic pt present w/hypoglycemia but low levels of C-peptide. What is the diagnosis?
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Surreptitious insulin injection
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Patient's MRI shows filling of sella turcica w/CSF. What is the most likely clinical presentation?
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Normal. Residula pituitary tissue is fxnal & can compensate. Empty sella syndrome
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Pateint complains of double vision, gynecomastia, & headaches. What is the most likely dx?
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Prolactinoma
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Patient presents w/hypotension and bronzed skin. What is the most likely dx?
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Primary adrenocortical deficiency - Addison's Dz
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What are the 3 zones of the adrenal cortex?
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Zona Glomerulosa, Zona Fasciculata, Zona Reticularis
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What stimulates the zona glomerulosa, causing it to secrete what?
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Stimulated by: Renin-Ang Secretes: Aldosterone
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What stimulates the zona fasciculata, causing it to secrete what?
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Stimulated by: ACTH, hypothalamic CRH Secretes: Cortisol& sex hormones
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What stimulates the zona reticularis, causing it secrete what?
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Stimulated by: ACTH, hypothalamic CRH Secretes: adrogens
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The adrenal cortex is derived from what tissue layer embryonically?
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mesoderm
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The medulla comes from what cells embryonically?
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neural crest cells
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What stimulates the medulla, causing it to secrete what?
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Stimulated by: Preganglionic sympathetic fibers Secretes: catecholamines ie: Epi, NE
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What cells in the medulla create the catecholamines?
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chromaffin cells
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First Aide helpful saying: The deeper you go the sweeter it gets relates to:
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GranulosaFasciculataReticularis corresponds with Salt (Na+), Sugar (glucocorticoids), and Sex ( androgens).
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Most common tumor of the adrenal medulla in adults
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pheochromacytoma
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most common tumor of adrenal medulla in kids
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Neuroblastoma
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Sxs of pheochromcytoma
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episodic HTN, not present in neuroblastoma
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The drainage pattern for the left adrenal:
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left adrenal -> left adrenal v -> left renal v -> IVC
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The drainage pattern for the right adrenal:
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right adrenal -> R adrenal v -> IVC
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The drainage of adrenals is synonomous with:
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same as left & Righ gonadal v
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What is posterior pituitary gland derived from
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neuroectoderm
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Another name for the posterior pituitary?
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neurohypophysis
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The neurohyposis releases what hormones?
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vasopressin (ADH) & oxytocin
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Where are the hormones released by the neurohypophysis made?
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the hypothalamus, there shipped to the pituitary
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Another name for the anterior pituitary?
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adenohypophysis?
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What hormones does the adenohyposis release?
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FLAT PiG: FSH, LH, ACTH, TSH, Prolactin, GH
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Where is MSH released from?
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the pars intermedia
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The anterior pituitary is derived from what embrologically?
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Oral ectoderm - Rathke's pouch
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Which adenohypophyseal hormones come from acidophils?
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GH & Prolactin
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Which adenohypohphyseal hormones come from basophils?
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B-Flat Basophils: FSH, LH, ACTH, TSH
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Which subunit of adenohyophyseal hormones determines specificity?
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Beta- subunit
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What adenohyophyseal hormones have the same alpha-subunit?
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TSH, LH, FSH, & hCG - think hot (TSH) sex (FSH, LH, hCG)
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What cell are endocrine cell nests of the pancreas?
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Islet of Langerhans
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What cells make up the Islets of Langerhans?
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alpha - located at periphery of islet , beta - located central in islet, & delta - interspersed throughout islet endocrine cells
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Where are the endocrine cells of the pancreas most numerous?
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the tail of the pancreas
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What do the islet cells arise from?
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pancreatic buds
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What do alpha endocrine cells of the pancrease secrete?
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glucagon
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What do beta endocrine cells of the pancrease secrete?
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INSULIN
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What do delta endocrine cells of the pancrease secrete?
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Somatostatin
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What causes the inhibition of release of prolactin?
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DA from the hypothalamus
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What stimulates prolactin release?
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TRH
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What chemical does prolactin stimulate?
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Increased synthesis and release of DA from hypothalamus
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What DA agonist medications due to PRL secreation, an example?
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Inhibit secretion, Bromocriptine
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What effect do DA antagonists have on PRL secretion, an example?
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stimulate secretion, antipsychotic
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What is the common sx in females with a Prolactinoma?
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amenorrhea: PRL inhibits GnRH synthesis & release, which I ovulation.
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TRH cause the release of which hormones from the pituitary?
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TSH and Prolactin
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DA has what effect on the pituitary?
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Inhibits prolactin release
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What stimulates the release of ACTH?
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CRH
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What causes the releas of GH hormone from the pituitary?
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GHRH
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SST has what affect on the pituitary?
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Inhibits GH & TSH release
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FSH & LH release is stimulated by what hypothalamic hormone?
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Pulsatile GnRH
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Cholesterol --> _________ via action of ____________ enzyme
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Pregnenolone; Desmolase
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Desmolase is stimulated by ____________?
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ACTH
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Desmolase is inhibited by _____________?
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Ketoconazole
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Pregenolone goes to these 2 products via these 2 different Es?
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1. Pregnenolone ------> 17-OH-pregnenolone via 17alpha-OHase ---> DHEA 2. Prenenolone - - - -> Progesterone via 3-beta-hydroxysteroid dehyrogenase
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3beta hydroxysteroid dehydrogenase cause DHEA to become _____?
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Androstenedione
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Androstenedione becomes __________ via ________ E.
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1. TESTOSTERONE via 21-Ohase
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Androstenedione and Testorone are converted by aromatase to:
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Estrone & Estradiol
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What enzyme converts testosterone to DHT?
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5alpha-reductase
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17-OH-progesterone comes from what 2 precursors via which respective Es?
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1. 17-OH-pregnenolone via 3beta-hydroxysteroid 2. Progesterone via 17alpha-OHase
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17-OH progesterone can become what 2 adrenal steroids?
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1. Androstenedione 2. 11- deoxycortisol
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What are the 2 precursors of Androstenedione?
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1. 17alpha-hydroxyprogesterone 2. DHEA
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What enzyme converts 11-deoxycortisol to cortisol?
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1. 11beta-OHase
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17-OH progesterone ---> 11-deoxycortisol via _______ enzyme.
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21-OHase
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Progesterone is converted to what 2 adrenal steriods via their respective enzymes?
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1. 17a-OH-pregnenolone via 17alpha-OH ase 2. 11-deoxycorticosterone via 21-OHase
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11 beta-OH converts what 2 adrenal steroids into which 2 hormones, respectively?
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1. 11-deoxycortisol ---> cortisol 2. 11-deoxycorticosterone ---> corticosterone
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Corticosterone becomes __________ via _________ enzyme.
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Corticosterone ---> ALDOSTERONE via Aldosterone synthase
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What stimulates aldosterone synthase?
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Ang II
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The glomerulosa produces what kind of adrenal steroids?
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Mineralocorticoids, C21
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The fasciculata produces what kinds of adrenal steroids?
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Glucocorticoids, C21
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The reticularis produces what kind of adrenal steroids?
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Androgens, C19
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Where are Estrogens produced?
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In the periphery, C18
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What are 3 congenital adrenal hyperplasia?
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1. 17alpha-OHase 2. 21-OHase 3. 11beta-Ohase
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What adrenal steroids accumulate in 17alpha-OHase deficiency, which ones are low?
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1. Accumulate: Pregenenolone & Progesterone 2. Low/Absent: 17-OH- Pregnenolone & 17-OH-progesterone
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What the general sxs of 17alpha-OHase defiency ?
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Low sex hormones, low cortisol, high mineralocorticoids. Cx = HYPERtension, hypoK+, phenotypically F but no maturation
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What adrenal steroid accumulate in 21-OHase deficiency? Which ones are low?
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1. Accumulate: Progesterone & 17-alphaOH-progesterone Low: corticosterone & 11-deoxycorticosterone
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Which adrenal enzyme is the most commonly deficienty?
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21-OHase
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What are the general symptoms of 21-OH ase deficiency?
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Low cortisol, high ACTH, lowmineralocorticoids, high sex hormones. Cx = masculinization , female pseudohermaphroditism, HYPOtension, hyperK+, increase pRenin activity, & volume depletion. Salt wasting can lead to hypovolemic shock in newborn.
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What adrenal steroids accumulate in 11beta-OH ase deficency, which ones are low?
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Accumulate: 11-deoxycortisol & 11-deoxycorticosterone low/absent: cortisol & corticosterone
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What are the general symptoms of 11-beta OH ase deficiency?
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Low cortisol, low aldosterone & corticosterone, high sex hormone. Cx = masculinaztion, HYPERtension - 11-deoxycorticosterone is mineralocorticoid and is secreted in access.
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Which adrenal steroid E deficiencies cause masculinations?
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21-OH ase & 11-beta Ohase
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Which adrenal steroid E deficiencies cause hypotension?
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21-OH ase
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Which adrenal steroid E deficiences cause hypertension?
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11-beta OH ase & 17-beta OH ase
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Which adrenal steroid E deficiency cause salt wasting in new borns?
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21-OH ase
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What makes PTH?
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Chief cells in the 4 parathyroid glands
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What affect does PTH have on bone?
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1. Stimulates Ca release from bone mineral compartment 2. Directly stimulast osteoblastic cells, indirectly stimualtes osteoclastic cells 3. Stimulates bone resportion via indirect stimulation of osteoclasts 4. Enhances bone matrix degradation
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What affect does PTH have on renal tubular cells
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1. Stimulates reabsorption of Ca 2. Inhibits PO4- resorption 3. Increases urinary cAMP 4. Stimulates production of 1,25-OH2-VitD
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What affect does 1,25-OH2-VitD have?
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Increase intestinal Ca absorption & causes release of PO4- from bone matrix
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what is PTH overall affect?
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Increases sCA
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PTH release is inhibited by what?
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high sCa levels
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PTH release is stimulated by?
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low free sCa levels
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What are the 4 general functions of PTH?
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1. Increase bone resporiton of Ca & PO4- 2. Increase kidney reaborption of Ca in dCT 3. Decrease kidney resorption of PO4- 4. Increase 1,25-OH2-VitD production by stimulating kidney 1-alpha- OH ase
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First aide helpful hint: PTH
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Phosphate Trashing Hormone
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PTH stimulates which 2 bone cell types:
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osteoclasts & osteoblasts
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PTH general affects on Ca & PTH:
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increase sCa, decrease sPO4-, increase uPO4-
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Low sPO4- has what affect on the kidney?
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increases conversion of 25-OH-D ----> 1,25 - OH2-D
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What are the sources of VitD?
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1. Sun exposure in skin 2. D2 ingested from plants
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Where doesthe hydroxylation conversion of VitD take place?
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liver- 25 - OH
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Where is the active form of VitD made?
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In the kidney by 1-alpha-OH ase.
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What are the 3 functions of Vit D?
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1. Increase absorption of dietary Ca, 2. Increase absorption of dietary PO4-, 3. Increase bone resorption of Ca & PO4-
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What are the regulators of VItD, and what are there affects?
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1. increased synthesis: PTH, low sCa & sPO 2. Inhibition: high 1,25-OH2-VitD
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Childhood dz with too little VitD
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rickets
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Adult dz with too little VitD
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Osteomalacia
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24,25-VitD is an _________ form of VitD
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inactive
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What are the Ca, PTH, AlkP, and PTH levels in hyperparathyroidism?
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Ca: high; PO4-: low; AlkP: high; PTH: high
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What are the Ca, PTH, AlkP, and PTH levels in Paget's dz of the bone?
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Ca: n/high; PO4-: N; AlkP: VERY HIGH; PTH: N
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What are the Ca, PTH, AlkP, and PTH levels in VitD intoxification?
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Ca: high; PO4-: high; AlkP: n/high; PTH: low
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What are the Ca, PTH, AlkP, and PTH levels in Osteomalacia?
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Ca: low; PO4-: low; AlkP: high ; PTH: high
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What are the Ca, PTH, AlkP, and PTH levels in Osteopeorosis?
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Ca: N; PO4-: N; AlkP: N ; PTH: N
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What are the Ca, PTH, AlkP, and PTH levels in Renal Insufficiency?
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Ca: low; PO4-: high; AlkP: N ; PTH: high
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Calcitionin comes from what cell type and where?
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Parafollicular cells of the thyroid
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What is the function of calcitionin?
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Decreases bone resorption of Ca
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What does high Ca do to calcitonin release?
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causes its release
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PTH is opposed by:
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Calcitionin
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Calcitonin is or is not important in Ca homeostasis?
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IS NOT
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acute manifestations of DM
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Polydipsia, polyuria, polyphagia, wt loss, DKA (T1) hyperosmolar coma (T2)
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chornic manifestations of DM
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nonenzymatic glycosylation (small/large vessels) and osmotic damage (neuropathy/cataracts)
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Key histological finding in DM
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Kimmelstein wilson nodules
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T1DM (IDDM) cause and HLA association
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viral or immune destruction of beta cells. HLA DR3 and 4
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T2DM (NIDDM) cause and HLA association
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Increased resistance to insulin. None
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Diabetic ketoacidosis signs
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Kussmaul respirations, psychosis, fruity breath, nausea/vomit
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Diabetic ketoacidosis Labs
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Hyperglycemia, anion gap met acidosis, hyperK+ but dec intracellular K+
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Diabetic ketoacidosis complications
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Mucormycosis, Rhizopus infections, cerebra edema, arryhtmias and HF
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Diabetic ketoacidosis treatment
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Fluids, insulin and potassium, glucose if necessary
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Diabetes insipidus diagnosis
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water deprivation test--> urine osmolality doesn't increase
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Diabetes insipidus desmopressin
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Response distinguishes between central and nephrogenic
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Diabetes insipidus findings
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urine specific gravity < 1.006, serum osmolality > 290 mOsm/L
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Diabetes insipidus treatment
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Central (untranasal desmopressin) nephrogenic (hydrocholorothiazide, indomethacin or amiloride)
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SIADH findings
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XS water retention, Hyponatremia, Urine osmolarity> serum osmolarity
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SIADH causes
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Ectopic ADH (small cell lung CA), CNS disorder/head trauma, Pulm dz, Drugs (cyclophosphamide)
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Carcinoid syndrome findings
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diarrhea, flushing, asthmatic wheezing, rt sided valve dz (MC tumor of appendix) Inc 5-HIAA in urine
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Carcinoid syndrome prognosis and Rx
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1/3 mets, 1/3 present with 2nd malignancy, 1/3 have multiple treat with octreotide
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Zollinger Ellison syndrome cause
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Gastrin secreting tumor of pancreas or duodenum. May be assoc with MEN type 1
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Insulin Aspart mechanism and use
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short acting, binds insulin receptor, treats T1DM, life threatening hyperK+ and stress induced hyperglycemia
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Insulin Aspart toxicity
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Hypoglycemia, hypersensitivity rxn (rare)
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Glipizide mechanism
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close K+ channels--> cell depolarizes-->triggers insulin release via Ca2+ influx
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Glipizide toxicity
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Hypoglycemia
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Glipizide use
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sitimulates release of endogenous insulin in T2DM. Useless in T1DM bc needs funcitonal islets
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Metrofmin toxicity
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Lactic acidosis
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Metformin mech
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unknown, possibly decreases gluconeogeneis, inc glycolysis and dec serum glucose levels
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Metformin use
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oral hypoglycemic, can be used in pts without islet function
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Rosiglitazone mech
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Increase target cell response to insulin
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Rosiglitazone use
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Monotherapy in T2DM or combined with other drugs
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Rosiglitazone toxicity
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wt gain, edema, hepatotox, CV tox
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Ascarbose mech
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Inhibit intestinal brush border alpha glucosidases, delated sugar hydrolysis and glucose abs
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Ascarbose use
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monotherapy in T2DM or in combo with others
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Ascarbose toxicity
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GI disturbance
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Orlistat mech
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alfters fat metab by inhibiting pancreatic lipases
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Orlistat use
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long term obesity management (with modified diet)
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Orlistat toxicity
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Steatorrhea, GI discomfort, reduced abs of fat sol vitamines, headache
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Sibutramine mech
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sympathomimetic serotonin and NE reuptake inhibitor
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Sibutramine use
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short term and long term obesity management
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Sibutramine toxicity
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HTN and tachycardia
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Propylthiouracil, methimazole mech
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Inhibit organification and coupling of thyroid hormone synthesis, PTU also dec periph conversion
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Propylthiouracil, methimazole use
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Hyperthyroidism
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Propylthiouracil, methimazole toxicity
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skin rash, agranulocytosis, aplastic anemia
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GH use
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GH deficiency, Turner's syndrome
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Somatostatin use
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(Octerotide) Acromegaly, carcinoid, gastrinoma, glucagonoma
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Oxytocin use
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Stimulates labor, uterine contraction, milk let down, controls uterine hemorrhages
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ADH use
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(desmopressin) Pituitary (central, not nephrogenic) DI
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Levothyroxine, triiodothyronine mech
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Thyroxine replacement
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Levothyroxine, triiodothyronine use
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Hypothyroidism, myxedema
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Levothyroxine, triiodothyronine toxicity
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Tachycardia, heat intolerance, tremors, arrythmias
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Glucocorticoids mech
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Decrease production of LTs and PGs by inhibiting PLA2 and expression of COX-2
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Glucocorticoids use
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Addisons dz, inflammation, immune suppression, asthma
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Glucocorticoids toxicity
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Iatrogenic cushings syndrome: buffalo hump, moon faces, truncal obesity, muscle wasting, thin skin
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