Estradiol, testosterone, and androstenedione in ovine follicular fluid during growth and atresia of ovarian follicles

Abstract

Measurement of estradiol-17β, testosterone, and androstenedione in follicular fluid obtained from groups of antral follicles of known diameter and stage of morphological atresia indicates two phases of steroidogenesis during nonatretic growth. In pools of fluid obtained from follicles of 1 to 3 mm diameter, a transient fourfold increase in testosterone concentrations form 99 to 420 nM was observed soon after antrum formation, whereas concentrations of androstenedione and estradiol-17β ranged from 4 to 16 and 10 to 47 nM, respectively. In the pooled fluid of nonatretic follicles of greater than 3 mm diameter, concentrations of estradiol-17β exceeded that of either testosterone or androstenedi..