THE EFFECT OF ENDOGENOUS OESTROGEN ON PLASMA AND URINARY CALCIUM AND PHOSPHATE IN OOPHORECTOMIZED WOMEN

Abstract
Using a specific radioimmunoassay, significant levels of plasma estradiol can be detected in the blood of oophorectomized women. In these women the plasma concentration of estradiol correlates positively with the body fat content. Low circulating concentrations of estradiol are associated with increased values for serum phosphate and alkaline phosphatase, but no significant change in serum Ca. The fasting urinary Ca creatinine ratio is inversely related to circulating plasma estradiol concentration which also correlates, in a more complex way, with the renal threshold for phosphate. Estrogen production may be an important factor in determining bone loss in postmenopausal women.