THE METABOLIC-FATE OF [H-3] ESTRADIOL IN RELATION TO DIETARY-INTAKE OF BORON IN OVARIECTOMIZED RATS

It has been reported that boron (B) deprivation reversibly lowers plas ma estradiol levels in postmenopausal women. In order to establish whe ther this reflects disturbances in the estrogen catabolic pathway and in particular in catechol estrogen metabolism, the influence of dietar y B on the catabolism of [H-3]estradiol-17beta has been studied in ova riectomized rats. Rats were given diets containing < 0.1 or 40 mg B. k g-1, ovariectomized and then infused with [H-3]estradiol-17beta using osmotic pumps. Analysis of urine samples for conjugated, catechol and non-catechol estrogens did not reveal any effects of B on the recovery or the metabolic fate of tritium from the infused estradiol. These re sults do not therefore support the proposal that B influences estrogen catabolism by interacting with catechol estrogens.