NUTR-4550 Lecture Notes - Lecture 25: Homeostasis, Whole Wheat Bread, Calcitriol Receptor
Document Summary
Calcium and calmodulin will change the form of a protein when bound: once bound, the inactive protein will become active. Parathyroid glands are found embedded in the thyroid. Calcium receptors will signal pth secretion/halt of secretion: up-regulation of the parathyroid occurs when calcium is low in the blood. Caused by increased 1-a-hydroxylase secretion from the kidney: makes dihydroxy d3 which can alter genes and cause calcium reabsorption. Reabsorption will occur through the small intestine and increase the blood calcium levels. Demineralization: rankl is the receptor for nf kappa b. Pth, prolactin, corticosteroids, etc: leads to maturation of osteoclasts. Mature osteoclasts on rankl will accumulate: becomes activated, embeds in the bone, and will remove minerals and release to plasma. Remineeralization: estrogens, calcitonin, calcium, p-d gf. Signal remineralization by binding to ogp to inhibit the maturation of osteoclasts. It will increase the osteoblast maturation (blast=build) which will deposit minerals from blood plasma onto bone. 1000 mg calcium come into the body.
