Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
|
what are the hypothlamus releasing factor and their effects?
|
1. Thyroid-stimulating hormone releasing hormone (TRH) --> TSH
2. corticotropin-releasing hormone --> ACTH 3. Growth hromone releasing hormone. --> GH 4. Gonadotrophin releasing hormone --> LH & FSH 5. somatostatin -X-> GH 6. PIF -X-> prolactin |
|
|
what are the effect of GH?
|
GH
main 5 effects: 1.stimulate chondrogenesis. 2.increase insulin secretion. 3.increase lipolysis in adipocytes. 4.increase absorption of Ca++ and PO from small intestine and mobilised them to growing bones. 5.promote mitosis 6.liver: produce small protein SOMATOMEDIN as intermediate to exert GH effect. |
|
|
what are effects of prolactin?
|
1. together with other hormones --> stimulate groth of mammary gland and mlk formation.
2. decrease progesterone secretion by corpus luteum. 3. inhibits LH formation and secretion. |
|
|
what are the feedback loops of hypothalamus-pituitary system?
|
Hypothalamic-pituitary (H-P)
1.H-P thyroid axis 2.H-P gonadal axis 3.H-P adrenal axis |
|
|
what's the nucleus that neurosecrete oxytoxin?
|
paraventricular nucleus of hypothalamus.
|
|
|
what is the nucleus that neurosecrete vasopressin?
|
supraoptic nucleus of hypothalamus.
|
|
|
what are the effect of oxytoxin?
|
1.triggers [Ca++]i result in myoepithelial of breast contraction --> squeeze milk out.
2.stimulate contraction of uterine muscle. |
|
|
what are the effect of vasopressin?
|
1. increase water reabsorption in kidney.
2. increase renal blood flow in medulla. 3. stimulate thirst centre. |
|
|
describe the hypophyseal portal system.
|
-hypophyseal artery ramifiy @ lower hypothalamus into capillary bed which takes up the hormones released by hypothalamus at median eminence.
-drain into hypothalamic-hypophyseal vein (down stalk) -drain into capillary again within anterior pituitary again which stimulate or inhibit the secretion of ant.pituitary hormones. -coalesce into vein which drain into systemic vein along with post.pituitary vein. |
|
|
what are the function of hypothalamus?
|
1. control lower ANS in brainstem and spinal cord.
2.control centre of endocrine system. 3.regulate body temp. 4.intake of food and water. 5.biological rhythm. 6.emotion 7.sexal arousal. |
|
|
what are the regions of hypothalamus in medial zone?
|
-preoptic: rostral to optic chiasm.
-supraoptic: above optic chiasm. -tuberal: between stalk and mammillary bodies. -mamiillary: anterior to mamillary bodies. |
|
|
what are the 2 components of pituitary gland and their origin?
|
1. adenohypophysis: oral ectoderm (Rathke's pouch)
2.neurohypophysis: neural ectoderm (down growth of diencephalon) |
|
|
blood supply of pituitary gland?
|
2 pairs:
1. Rt and Lt superior hypophyseal artery supply: -median eminence -infundibulum 2.Rt and Lt inferior hypophyseal artery supply: -mostly pars nervosa. |
|
|
what are multiple effects of cortisol?
|
1.anti-insulin
2.alters metabolic reactions in stress. 3.anti-inflammatory 4.increase in free water clearance 5.increase BP 6.stimulate polycynthemia 7.suppress immune system 8.increase Na+ reabsorption |
|
|
what happen when cortisol in excess?
|
-glucose intolerance
-redistribution of adipose tissues -cushings' |
|
|
what are the major CONTROL MECHANISM of mineralocorticoids synthesis?
|
1. renin-angiotensin system
2. potassium 3. hyponatremia |
|
|
what are the functions of mineralocorticoids?
|
-sustain extracellular fluid volume
-stimulate sodium uptake |
|
|
effect of androgen?
|
-increase protein synthesis
-promote male 2nd sexual appearance -defiminisation -masculination |
|
|
what are the cathecolamines?
|
-dopamne
-epinephrine/adrenaline -norepinephrine/noradrenaline |
|
|
what is the precursor for cathecolamines?
|
-tyrosine
|
|
|
what is tyrosine of?
|
-phenylalanine
-synthesized in the liver -from diet |
|
|
how does tyrosine form cathecolamines?
|
1.hydroxylation of tyrosine.
-form: dehydroxyphenylalanine (DOPA) 2.decarboxylation of DOPA -form: dopamine |
