{"content"=>"Local production of neurostradiol affects gonadotropin-releasing hormone (GnRH) secretion at mid-gestation in (Rodentia, Caviomorpha).", "i"=>{"content"=>"Lagostomus maximus"}} (original) (raw)

Females of the South American plains vizcacha, , show peculiar reproductive features such as massive polyovulation up to 800 oocytes per estrous cycle and an ovulatory process around mid-gestation arising from the reactivation of the hypothalamic-hypophyseal-ovary (H.H.O.) axis. Estradiol (E) regulates gonadotropin-releasing hormone (GnRH) expression. Biosynthesis of estrogens results from the aromatization of androgens by aromatase, which mainly occurs in the gonads, but has also been described in the hypothalamus. The recently described correlation between GnRH and ER expression patterns in the hypothalamus of the vizcacha during pregnancy, with coexpression in the same neurons of the medial preoptic area, suggests that hypothalamic synthesis of E may affect GnRH neurons and contribute with systemic E to modulate GnRH delivery during the gestation. To elucidate this hypothesis, hypothalamic expression and the action of aromatase on GnRH release were evaluated in female vizcachas t...