Local effect of allopregnanolone in rat ovarian steroidogenesis, follicular and corpora lutea development

CÁCERES ANTONELLA ROSARIO RAMONA; CARDONE, DANIELA ALEJANDRA; SANHUEZA, MARIA DE LOS ANGELES; BOSCH, IGNACIO; CUELLO CARRION, D; RODRIGUEZ, GRACIELA BEATRIZ; SCOTTI L; PARBORELL, FERNANDA; HALPERIN, JULIA; LACONI MYRIAM RAQUEL

Scientific Reports

Nature Research

Año: 2024 vol. 14

Allopregnanolone (ALLO) is a known neurosteroid and a progesterone metabolite synthesized in theovary, CNS, PNS, adrenals and placenta. Its role in the neuroendocrine control of ovarian physiologyhas been studied, but its in situ ovarian efects are still largely unknown. The aims of this work wereto characterize the efects of intrabursal ALLO administration on diferent ovarian parameters, andthe probable mechanism of action. ALLO administration increased serum progesterone concentrationand ovarian 3β-HSD2 while decreasing 20α-HSD mRNA expression. ALLO increased the number ofatretic follicles and the number of positive TUNEL granulosa and theca cells, while decreasing positivePCNA immunostaining. On the other hand, there was an increase in corpora lutea diameter and PCNAimmunostaining, whereas the count of TUNEL-positive luteal cells decreased. Ovarian angiogenesisand the immunohistochemical expression of GABAA receptor increased after ALLO treatment. Toevaluate if the ovarian GABAA receptor was involved in these efects, we conducted a functionalexperiment with a specifc antagonist, bicuculline. The administration of bicuculline restored thenumber of atretic follicles and the diameter of corpora lutea to normal values. These results show theactions of ALLO on the ovarian physiology of the female rat during the follicular phase, some of themthrough the GABAA receptor. Intrabursal ALLO administration alters several processes of the ovarianmorpho-physiology of the female rat, related to fertility and oocyte quality.