The Effect of Hypercalcemia Induced by Calciferol Upon Renal Concentrating Ability1

Abstract

Hypercalcemia was induced in rats by 4 daily injections of 200,000-400,000 units of calciferol (vitamin D2). Renal concentrating ability was markedly impaired, although there was little or no changein blood urea, urea clearance or excretion of phenolsulfonphthalein. Morphological changes in the kidneys were sparse and consisted chiefly of lesions involving the collecting ducts in the outer medulla. It is suggested that similar alterations in renal structure and function may be responsible for the polyuria and hyposthenuria observed in a variety of clinical states associated with hypercalcemia or nephrocalcinosis.