1982 Volume 29 Issue 6 Pages 725-731
A 37-year-old woman with postoperative hypoparathyroidism had hypertension, and elevated plasma renin activity (PRA) and subsequent hyperaldosteronism during a twomonth hypercalcemic period caused by vitamin D and excessive calcium supplements. The hypertension with elevated PRA, however, was resistant to the angiotensin II (AII) analog [Sar1, Ile8] AII. PRA further increased and plasma aldosterone decreased in response to the [Sar1, Ile8] AII. When the patient became normocalcemic, normotensive and normoreninemic, calcium gluconate (5mg calcium/kg/h) was infused for one hour. The calcium infusion reproduced hypercalcemic hypertension mediated by an increase in total peripheral resistance.
These observations suggest that the hypertension observed while taking vitamin D and excessive calcium supplements may be caused by a direct effect of calcium on peripheral blood vessels and the renin-angiotensin system may play a negligible role.
