title: The impact of acute ethanol on reproductive hormone synthesis, processing, and secretion in female rats at proestrous.
abstract: It is the purpose of this study to investigate the effects of acute ethanol (EtOH) on the female rat hypothalamic-pituitary-gonadal (HPG) axis. The molecular and cellular mechanistic details of such effects have been studied intensively in the male rat. However, there has been relatively little in-depth study of EtOH's effects on the adult, postpubertal female rat. Adult female rats with confirmed 4- or 5-day estrous cycles were given a single injection of EtOH or saline between noon and 1:00 PM on proestrous and were killed at 4:00 PM. EtOH caused a sharp 97% reduction in luteinizing hormone (LH) serum levels (p < 0.001), compared with controls with no concomitant change in LH mRNA. EtOH also significantly reduced hypothalamic LH releasing hormone (LHRH) by 49% (p < 0.01), with no change in content of the precursor pro-LHRH compared with saline-injected controls. The ratio of LHRH to pro-LHRH was also significantly reduced by EtOH (p < 0.05), compared with control. There was no EtOH-induced change in LHRH mRNA. Compared with saline, EtOH reduced both serum estradiol by 37% (p < 0.02) and progesterone by 47% (p < 0.001). These results show that EtOH has profound disruptive effects on the female HPG axis. Our data suggests that EtOH decreases the releasable LHRH pool either by decreasing conversion of pro-LHRH to LHRH and/or by increasing local LHRH degradation. This acutely restricts the release of LH and subsequent estradiol and progesterone secretion.
authors.affiliation: Department of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: N
authors.initials: N
authors.lastname: LaPaglia
authors.forename: J
authors.initials: J
authors.lastname: Steiner
authors.forename: L
authors.initials: L
authors.lastname: Kirsteins
authors.forename: M A
authors.initials: MA
authors.lastname: Emanuele
authors.forename: N
authors.initials: N
authors.lastname: Emanuele
mesh_terms: D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D004958:Estradiol / Q000378:metabolism; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D007987:Gonadotropin-Releasing Hormone / Q000097:blood* / Q000378:metabolism; D007986:Luteinizing Hormone / Q000097:blood* / Q000378:metabolism; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011359:Proestrus / Q000187:drug effects / Q000378:metabolism*; D011374:Progesterone / Q000097:blood* / Q000378:metabolism; D011498:Protein Precursors / Q000097:blood / Q000378:metabolism; D012333:RNA, Messenger / Q000302:isolation & purification / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D014158:Transcription, Genetic
chemical_list: D011498:Protein Precursors; D012333:RNA, Messenger; C050866:progonadoliberin I; D007987:Gonadotropin-Releasing Hormone; D000431:Ethanol; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone