IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Allopregnanolone alters follicular and luteal dynamics during the estrous cycle
Autor/es:
ÁNGELES SANHUEZA; ANTONELA CÁCERES; MYRIAM LACONI; JOANA ASENSIO; LAURA PELEGRINA
Lugar:
Concón
Reunión:
Workshop; 4th International Workshop of Neuroendocrinology; 2017
Institución organizadora:
International Workshop of Neuroendocrinology
Resumen:
Allopregnanolone is a neurosteroid synthetized in the central nervous system independently of steroidogenic glands, and it influences sexual behavior and anxiety. Experiments were designed to evaluate the effect of a single pharmacological dose of allopregnanolone on folliculogenesis, apoptosis, proliferation and angiogenesis. The endocrine profiles and enzymatic activities of critical steroidogenic proteins were determined. Allopregnanolone was injected during proestrous morning, and then the animals were sacrificed at each stage of the estrous cycle. Ovarian sections were processed to determine the number and diameter of different ovarian structures. Cleaved caspase 3, proliferating cell nuclear antigen, α-actin and von Willebrand factor expressions were evaluated by immunohistochemistry. Luteinizing hormone, prolactin, estrogen and progesterone serum levels were measured by radioimmunoassay. The enzymatic activities of 3β-hydroxysteroid dehydrogenase, 3α-hydroxysteroid oxidoreductase and 20α-hydroxysteroid dehydrogenase were determined by spectrophotometric assays. Developing follicles decreased, while atretic follicles and cysts increased in treated rats. Some cysts showed characteristics of luteinized unruptured follicles. Apoptosis/proliferation balance increased in follicles, and this was associated to a decrease in estrogen serum levels. Prolactin, estrogen and serum levels were altered at different stages of the estrous cycle of treated rats. Allopregnanolone inhibited LH surge and generated cysts without affecting normal cyclicity. Angiogenic markers expression increased in treated ovaries. Apoptosis/proliferation balance and 20α-hydroxysteroid dehydrogenase enzymatic activity were decreased in corpora lutea, thus luteolysis process was delayed. Progesterone levels and 3β-hydroxysteroid dehydrogenase were increased in treated rats. These results suggest that allopregnanolone interferes with folliculogenesis and steroidogenesis processes and it also promotes corpora lutea survival and progesterone synthesis.