In human granulosa cells from small antral follicles, androgen receptor mRNA and androgen levels in follicular fluid correlate with FSH receptor mRNA

Human small antral follicles (diameter of 3-9 mm) were obtained from ovaries surgically removed for fertility preservation. From the individual aspirated follicles, granulosa cells and the corresponding follicular fluid (FF) were isolated in 64 follicles, of which 55 were available for mRNA analysis (24 women). Expression of Androgen Receptor (AR) mRNA levels in granulosa cells, and of androstenedione and testosterone in FF, were correlated to the expression of FSH receptor (FSHR), LH receptor (LHR), CYP19 and anti-Müllerian Hormone-receptor2 (AMHR2) mRNA in the granulosa cells and to the FF concentrations of AMH, inhibin-B, progesterone and estradiol. Androgen Receptor mRNA expression in granulosa cells, and the FF content of androgens, both showed a highly significant positive association with to the expression of FSHR mRNA in granulosa cells. AR mRNA expression also correlated significantly with the expression of AMHR2, but did not correlate with any of the hormones in the FF. These data demonstrate an intimate association between AR expression in immature granulosa cells, and the expression of FSHR in normal small human antral follicles and between the FF levels of androgen and FSHR expression. This suggests that follicular sensitivity towards FSH stimulation may be augmented by stimulation of androgens via the AR.