Parathyroid And Calcium Regulation

Front 1

Discuss the organs involved in calcium regulation.

Back 1

Bone
kidney
intestinal absorption

Front 2

List the three forms of calcium and their relative forms.

Back 2

protein bound (biologically inactive) 40%
ionized (free) 50%
complexed w/phosphate bicarbonate and citrate 10%

Front 3

only____ is biologically active. -neuromuscular activity, enzyme activation coagulation.

Back 3

ionized calcium

Front 4

______ binds calcium loosely.
acts as a circulating reservoir.

Back 4

Albumin

Front 5

Non ionized calcium salts are filtered by _____ and cannot be reabsorbed... lost in urine

Back 5

kidney

Front 6

found in small amounts, plays a major role in muscle contraction, glycogen metabolism and enzyme activation.

Back 6

intracellular calcium

Front 7

3 hormones of regulation of Calcium

Back 7

Parathyroid hormone (PTH)
Vitamin D
Calcitonin

Front 8

Also known as "ACTIVE VITAMIN D)

Back 8

1,25 dihydroxychelcalciferol

Front 9

active vitamin D deficiency causes:

Back 9

ricketts in children and osteomalacia in adults

Front 10

Required by the transmembrance proteins (in intestine and PCT) that absorb calcium and phosphorus to increase absorption.

Back 10

active vitamin D

Front 11

________ is a protein; synthesized as an inactive precursor by parathyroid glands. Biological activity is in first ___ of 84 amino acid peptide.

Back 11

PTH (parathyroid hormone)
28

Front 12

PTH (_-terminal) has a short life in plasma (15-20minutes) breaks down into smaller inactive peptides

Back 12

N-terminal

Front 13

stimulus: decrease ionized calcium concentration stimulates ____ secretion.

Back 13

PTH

Front 14

enhances osteoclast activity in bones> release of ionized calcium and phosphorus into plasma and increases renal tubular reabsorption of calcium.

Back 14

PTH

Front 15

works with vitamin D to absorb Ca from food

Back 15

PTH

Front 16

inhibits transmembrane protein in PCT that reabsorb phosphorus.

Back 16

PTH

Front 17

Net effect :increase serum Ca, decrease serum P, increase urine P, negative feedback.

Back 17

PTH

Front 18

peptide hormone, produced from parafollicular or C-cells of thyroid gland. Stimulus increase calcium

Back 18

calcitonin

Front 19

inhibits osteoclast activity in bones> net synthesis of bone> removal of Ca from plasma (negative feedback)

Back 19

calcitonin

Front 20

inhibits tubular reabsorption of Ca and enhances renal excretion of Ca

Back 20

calcitonin

Front 21

net effect: decrease serum Ca and increase urine Ca

Back 21

Calcitonin

Front 22

symptoms of ______ include gastrointestinal symptoms, neurologic changes or in extreme cases, coma. untreated _____ may result in the production of kidney stones, (nephrolithiasis) and osteopenia.

Back 22

hypercalcemia

Front 23

the most frequen cause of hypercalcemia is _____ _____. Other cause of hypercalcemia include malignancy, sarcoidosis and hypervitaminosis of vitamin d and immobilization.

Back 23

primary hyperparathyroidism

Front 24

signs and symptoms of _______ include tetany, spasms, and convulsions.

Back 24

hypocalcemia

Front 25

causes of _______ include hypoparathyroidism, pseudohypoparathyroidism, vitamin D defiency, renal tubular disease, acute renal failure, gastrointestitinal malabsorption and acute pancreatitis

Back 25

hypocalcemia

Front 26

caused by adenoma or hyperplasia of the parathyroid gland. physiologic defect is with the parathyroid gland (primary). Very limited or no PTH response to negative feedback>> breakdown of bone>> increases calcium but also inhibits P reabsorption by PCT

Back 26

primary hyperparathyroidism

Front 27

net: serum has increased Ca, decrease Pi, increase ALP(bone), increase urine Ca and Pi, and increase PTH

Back 27

primary hyperparathyroidism

Front 28

symptoms include thinning of bones and fractures, altered mental status and kidney stones

Back 28

primary hyperparathyroidism

Front 29

PTH related protein is a protein produced by cancer cells that cause hypercalcemia. It is similar to the N terminal of PTH and acts like PTH.

Back 29

PTHrP

Front 30

both PTH and PTHrP bind to the same receptos in ___ and ____. PTH is ____ by PTHrP( causes increase Ca, decrease Pi, increase urine Ca and Pi. PTHrP does not respong to negative feedback.

Back 30

kidney and bone
suppressed

Front 31

PTH and PTHrP Do not cross react in _____.

Back 31

immunoassays

Front 32

parathyroid gland is normal and healthy. PTH is elevated due to a threat of hypocalcemia from drugs, chronic renal disease, vitamin D defiency, intestinal malabsorption, and etc.

Back 32

secondary hyperparathyroidism

Front 33

increase Pi,
decrease Ca due to decreased reabsorption, increase PTH in response to Ca>> increase ALP, vitamin D due to reduced synthesis as a result of inadequate renal mass. decrease protein and albumin, symptoms of hyperparathyroidism.

Back 33

chronic renal disease (secondary hyperparathyroidism

Front 34

some acute pancreatitis cases>> _______. due to released of fatty acids(increased ___ activity) which bind with Ca. decreased Ca absorption due to malabsorption can result in increase PTH production.

Back 34

acute hypocalcemia
lipase

Front 35

__________>> acute hypocalcemia. common in hospitalized patients. chronic Mg deficiency inhibits PTH secretion across the parathyroid gland membrane impairs PTH action to the receptor site on bone and causes ________.

Back 35

chronic hypomagnasemia
vitamin d resistance

Front 36

malabsorption (pancreatic insuffiency) may cause inadequate dietary absorption. severe liver or kidney diease> vit D deficiency. inadequate Ca absorption from diet>> osteoblasts are not able to produce hydrozyapatite>> soft pliable bone= ricketts in children

Back 36

vitamin D deficiency (secondary hyperparathyroidism)

Front 37

_____ _____ in plants binds vitamin D and prevents absorption.

Back 37

phytic acid

Front 38

Net: serum has decrease Ca, decrease Pi, increase ALP, increase PTH. can measure 1,25 DHCC in plasma

Back 38

vitamin D deficiency- secondary hyperparathyroidism

Front 39

hyposecretion of PTH. removal of parathyroid gland, trauma, radiation theraphy or thyroid, head or neck surgery. symptoms: tetany (muscle spasms) drying skin, brittle hair, hypotension and GI upset. decrease Ca, increase Pi, decrease PTH. treatment is high dose Ca and Vitamin D.

Back 39

primary hypoparathyroidism

Front 40

inherited tubular resistance to biological activity (defect in signnaling of the receptor) of PTH. increase PTH is produced as a result of hypocalcemia but cannot respond to decrease Ca.

Back 40

pseudohypoparathyroidism

Front 41

accumulation of Pi in plasma. increase of Pi, decrease in Ca, stimulates increase PTH> bone breakdown>(ALP increase) to restore Ca and decrease Pi excretion in urine. net: serum has borderline decrease Ca, increase Pi, increase ALP, PTH is N to increase, vit D also decrease due to lack of PTH response. symptoms thinning of bones=renal osteodystrophy.

Back 41

pseudohypoparathyroidism

Front 42

primary bone disorders. most often _____ cancer (breast, prostate, other). _____ disease(uncommon) is hyperactivity of osteoclasts> constant excessive remodeling of bone(thickened and missshapen bone surfaces. Tumor pressing of bone> breakdown and release of Ca and Pi, but increase Ca> inhibition of PTH: no stimulus to get rid of the extra Pi. Net serum has increase Ca, Pi, ALP and decrease PTH.

Back 42

metastic
Pagets disease

Front 43

Causes: Aging or inactivity (ex:long term bed rest, cast on broken bone)- reduction in bone mass (breakdown of collage) (bone resorption> bone formation) Labs: no abnormality in Ca, Pi, ALP, PTH or Vit D. increase pyridinoline in urine. Therapy to prevent fractures.

Back 43

Osteoporosis

Front 44

fluorescent cross-linking compound of collagen fibers.

Back 44

Pyridinoline, also known as Hydroxylysylpyridinoline.

Front 45

_____ method. Uses octyl-phenyl-phosphate as the ionophore.

Back 45

ISE METHOD

Front 46

sample for ISE method: not exposed to air, heparin to anticoagulant, on ice, less than 1hr old.

Back 46

whole blood of serum/plasma for Ca.

Front 47

dye binding method (______ method)

Back 47

arsenzo

Front 48

dye should be made selectively for Ca2+ by binding other ____ like Mg to a chelating agent.

Back 48

metals

Front 49

dye binds Ca more tightly than ____ or _____ and measures total Ca.

Back 49

albumin or anionic salts

Front 50

dye binding method. selectivity is also ___ dependent. Reference method: _____ ____ ____.

Back 50

pH
Atomic absorption spectroscopy

Front 51

reference range for Ca

Back 51

8.6-10mg/dL (adults)
8.6-10.6mg/dL (children)

Front 52

serum albumin levels must always be measure with ___ ____.

Back 52

total Ca

Front 53

At ph < ___, 8-hydroxyquinoline binds Ca2+, not Mg2+

Back 53

10

Front 54

sample for dye binding method : avoid ____ binding antocoagulants (EDTA, OXALATE, CITRATE AND ETC)

Back 54

calcium