Stage-dependent actions of antimüllerian hormone in regulating granulosa cell proliferation and follicular function in the primate ovary.

OBJECTIVE

To study the direct action and physiological role of antimüllerian hormone (AMH) in regulating ovarian follicular development and function in vivo in primates.

DESIGN

Animals were assigned to six treatment sequences in a crossover design study. Intraovarian infusion was performed during the follicular phase of the menstrual cycle with agents including: control vehicle; recombinant human AMH (rhAMH); and neutralizing anti-human AMH antibody (AMHAb). Before ovariectomy after the final treatment, the animals received intravenous injections of bromodeoxyuridine (BrdU).

SETTING

National primate research center.

ANIMALS

Adult female rhesus macaques ().

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Cycle length, follicle cohorts, and serum steroid levels were assessed. Ovarian histology, as well as granulosa cell (GC) proliferation and oocyte viability, were evaluated.

RESULTS

In vehicle-infused ovaries, a dominant follicle was observed at midcycle E peak. However, rhAMH-treated ovaries exhibited an increased number of small antral follicles, whereas AMHAb-treated ovaries developed multiple large antral follicles. Serum E levels in the follicular phase decreased after rhAMH infusion and increased after AMHAb infusion. The rhAMH infusion increased serum T levels. Whereas early-growing follicles of rhAMH-treated ovaries contained BrdU-positive GCs, antral follicles containing BrdU-positive GCs were identified in AMHAb-treated ovaries. Autophagy was observed in oocytes of early-growing and antral follicles exposed to AMHAb and rhAMH, respectively.

CONCLUSIONS

AMH enhanced early-stage follicle growth, but prevented antral follicle development and function via its stage-dependent regulation of GC proliferation and oocyte viability. This study provides information relevant to the pathophysiology of ovarian dysfunction and the treatment of infertility.