L5 biochem Flashcards
where is site of calcium absorption
first and second part of duodenum
source of calcium
animal: yogurt, milk, cheese
plant: vegetable, fruit
factor increase calcium absorption
vitamin D calcitriol
parathyroid hormone
high acidity
high protein diet like arginine and lysine
sugar and organic acid (increase solubility of calcium salt)
citric acid
factor decrease calcium absorption
high fat diet
excess phosphate
excess phytic acid
excess oxalates in mango and green leafy vegetable
excess fiber
increase pH or increase alkalinity
glucocorticoid
malabsorption syndrome
calcitonin (inhibit activation of vit D)
inflammatory intestinal condition
what are 3 main organ that important for regulation of plasma calcium or calcium homeostasis
bone kidney intestine
what are 3 main hormone in calcium regulation
increase serum calcium by;
-calcitriol
-parathyroid hormone
decrease serum calcium by
-calcitonin
what are the non hormonal in regulation of plasma calcium
acidosis
alkalosis (decrease)
hypoalbuminemia(decrease)
glucocorticoids (decrease)
explain how PTH increase calcium level and decrease phosphate level
kidney; increase reabsorption of Ca and decrease reabsorption of phosphate
bone; demineralization of bone, release of collagenase enzyme increase Ca release from the bone
intestine; activation of vit D increase synthesis of calbindine protein that carry calcium
what are the functions of calcium
-act as second messenger
-activation of enzyme (calmodulin protein)
-blood coagulation
-formation of bone and teeth
-prolong systole
-excitation and contraction of muscle
daily requirement of calcium g/day
adult -0.8
children-1.2
pregnancy and lactating mother- 1.5
causes of hypercalcemia (normal :9-11mg/dl)
-hyperparathyroidism
-overdose vitamin D
-bone metastases
-endocrine
-idiopathic in infant
describe causes of hypocalcemia below 8.8mg/dl
-hypoalbuminemia
-hypomagnesemia
-hypoparathyroidism
-vitamin D deficiency
-chronic liver and renal disease
what are the sources of phosphorus
plant; legume, soy bean, lentils
animal: liver kidney heart meat fish milk cheese
describe factor affecting plasma phosphorus
-PTH hormone (decrease)
-vitamin D (decrease phosphate release from bone)
-renal failure (increase)
describe functions of phosphorus
mineralization of bone and teeth
maintain pH
synthesis of phospholipid and phosphoprotein
component of DNA nad RNA
trap monosaccharides in the cells
