calcium homeostasis :'( Flashcards
name for higher than normal calcium levels
hypercalcemia
3 domains of activity
intake and excretion
storage
control
intake calcium?
calcium absorbed across brush border of intestinal epithelial cells, immediately binds to calbindin (vitamin D dependant protein)
what is calcitriol
active form of vitamin D, regulates calcium intake in intestines
what does calcium intake in the intestines depend on?
adequate vitamin D
calcium excretion?
via bile
what increases renal excretion and inhibits reabsorption
calcitonin - more calcium lost in urine
PTH effects on kidney?
reduces renal excretion (opposite of calcitonin) and processes vitamin D into calcitriol
what gland is calcitonin from
thyroid gland
how is calcium stored
hydroxyapatite in bones (99%)
what does release of calcium depend on
normal bone activity
what directly inhibits osteoclast activity?
calcitonin (from the thyroid gland)
what indirectly stimulates osteoclast activity
RANK-L from osteoblasts
what causes RANK-L to be released from osteoblasts
PTH
where is parathyroid hormone excreted from
parathyroid gland