title: The participation of the cholinergic system in regulating progesterone secretion through the ovarian-adrenal crosstalk varies along the estrous cycle.
abstract: This study was designed to analyze the acute effects of unilateral or bilateral ovariectomy or adrenalectomy, performed on different days of the estrous cycle, on progesterone (P4) serum levels 1 h after surgery. The effects of blocking the cholinergic system by injecting atropine sulfate were also analyzed. Ether anesthesia treatment on diestrus 1 (D1) increased P4 serum levels. Compared to right sham-operated animals, right ovariectomy (left ovary in situ) performed on diestrus 2 (D2) or proestrus (P), resulted in P4 serum levels increase. Compared to animals with left sham surgery, left adrenalectomy (right adrenal in situ) performed on P day resulted in significantly lower P4 concentrations. Bilateral adrenalectomy resulted in a significant drop of P4 serum levels; the most remarkable drop was observed in animals treated on D2. Bilateral ovariectomy performed on D1 resulted in lower P4 serum levels, and the same treatment performed on P resulted in a significant rise of P4 serum levels. Injecting atropine sulfate to untouched (control group) rats resulted in significantly higher P4 concentrations. Blocking the cholinergic sys-tem on D1 or P to rats with the right adrenal removed resulted in lower P4 serum levels; while, in contrast, atropine sulfate treatment performed on D2 resulted in P4 serum levels increase. The results support the hypothesis of asymmetry in the ovaries' and adrenals' capacities to secrete P4; that this capacity varies along the estrous cycle; and that P4 secretion by the ovaries and adrenals is regulated by the cholinergic system.
authors.affiliation: Biology of Reproduction Research Unit, FES Zaragoza, UNAM, México.
authors.forename: Angélica
authors.initials: A
authors.lastname: Flores
authors.forename: Griselda
authors.initials: G
authors.lastname: Meléndez
authors.forename: María T
authors.initials: MT
authors.lastname: Palafox
authors.forename: Jorge O
authors.initials: JO
authors.lastname: Rodríguez
authors.forename: Ana I
authors.initials: AI
authors.lastname: Barco
authors.forename: Roberto
authors.initials: R
authors.lastname: Chavira
authors.forename: Roberto
authors.initials: R
authors.lastname: Domínguez
authors.forename: M Esther
authors.initials: ME
authors.lastname: Cruz
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism*; D000315:Adrenalectomy; D000769:Anesthesia, Inhalation; D000818:Animals; D001285:Atropine; D018680:Cholinergic Antagonists; D030762:Estrous Cycle / Q000502:physiology*; D004986:Ether; D005260:Female; D009490:Neurosecretory Systems / Q000502:physiology*; D010052:Ovariectomy; D010053:Ovary / Q000378:metabolism*; D011374:Progesterone / Q000097:blood / Q000378:metabolism*; D051381:Rats
chemical_list: D018680:Cholinergic Antagonists; D004986:Ether; D011374:Progesterone; D001285:Atropine