Endocrine control of the intestinal calcium excretion

Calcium excretion from rat intestine was measured by placing distilled water in an intestinal loop in situ and measuring the calcium content after various intervals. More calcium was excreted from the intestine of 18-month-old rats than that of 1-month-old rat. Acute hypocalcemia failed to change the intestinal calcium excretion significantly. Parathyroidectomy decreased intestinal calcium excretion and administration of Parathyroid Extract reversed it. Renal damage produced by injection of Na-sulfacetylthiazole increased the intestinal calcium excreation but dihydrotachysterol reversed it. Gastrin at 200 microng/kg increased the intestinal calcium excretion. Calcium excretion, like calcium absorption, appears to be controled by various endocrine factors and the method of intestinal loop in situ appears to be useful to study the part played by these factors.