Relationship Between Estradiol and Parathyroid on Retention of Ca45 in Bone and Blood Serum of Rats.

Abstract

Administration of estrogen to normal male rats increased the radioactivity of blood serum following Ca45 injection, whereas bone remained unchanged. Parathyroid extract depressed radioactivity of both bone and blood serum but when estrogen was given in addition radioactivity was increased in both. Parathyroidectomy depressed the radioactivity of bones and serum but estrogen again increased the radioactivity of bones slightly and serum significantly. Data indicate that estrogen plays a role in Ca metabolism independent of the parathyroid hormone in aiding retention of Ca.