Calcium in kidney

Calcium is present in three forms e.g., as free calcium ion, bound to plasma protein albumin and in diffusable complexes. The endocrine system, through parathyroid hormone and calcitonin, helps in keeping the concentration of ionized plasma calcium in normal level. Decrease in plasma levels of ionized calcium leads to increased parathyroid hormone secretion. Parathyroid hormone tends to increase plasma calcium level by increasing bone resorption, increasing intestinal absorption and increasing reabsorption of calcium in kidney. Vitamin D acts by stimulating... 

Talalaj M, Gradowska L, Marcinowska-Suchowierska E, Durlik M, Gaciong Z, Lao M. Efficiency of preventive treatment of glucocorticoid-induced osteoporosis with 25-hydroxyvitamin D3 and calcium in kidney transplant patients. Transplant Proc 1996 28(6) 3485-7. 

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