The fate of intravenously administered calcium; effect on urinary calcium and phosphorus, fecal calcium and calcium-phosphorus balance
BAYLOR, C.H.; VAN ALSTINE, H.E.; KEUTMANN, E.H.; BASSETT, S.H.
Journal of Clinical Investigation 29(9): 1167-1176
1. Intravenously administered calcium gluconate (550 mg. Ca daily) was used to supplement the dietary intakes of three human subjects. These included an essentially normal woman, a woman with postmenopausal osteoporosis, and a man who was recovering from a period of partial starvation. 2. A considerable part of the calcium was excreted in the urine within 24 hours. 3. No consistent effect on fecal calcium could be demonstrated. 4. Some of the calcium was retained in each case. If one considers the urinary calcium alone, the retention was greatest in the male subject during repletion and least in the woman with osteoporosis. 5. Intravenous calcium was followed by a decrease in urinary calcium excretion in both female patients. It is suggested that this may have been caused by depression of the activity of the parathyroid glands. 6. Calcium decreased the excretion of phosphorus in the urine of all patients without increasing its fecal excretion. This effect is the converse of that observed when large doses of a soluble phosphate are given orally. 7. In the normal woman, steroid therapy (testosterone propionate and alpha estradiol benzoate) increased the retention of both the Ca and P absorbed from the food, but did not seem to increase the retention of the calcium supplement. 8. A small nitrogen-sparing effect was noted in the male subject and in the normal woman during periods when calcium gluconate was injected.