Changes In Parathyroid Hormone Secretion Research Articles

Studies on the mechanism of action of calciferol VII. Localization of 1,25-dihydroxy-vitamin D 3 in chick parathyroid glands

When 1,25(OH) 2-vitamin D 3 was administered to vitamin D-deficient chicks, within two hours the parathyroid glands were observed to accumulate this steroid to a concentration four times that present in the blood and equivalent to levels observed in the target intestine. Similarly, when 25-(OH)-vitamin D 3 was administered, the parathyroid glands had 2.4 times the concentration of the metabolite, 1,25-(OH) 2-vitamin D 3 as that seen in the blood and 60% of that found in the intestine. These results are consistent with the concept that the hormonally active form of vitamin D, 1,25-(OH) 2-vitamin D 3, may interact with the parathyroid glands to effect changes in parathyroid hormone secretion.