A gonadotrophin-releasing hormone (GnRH) antagonist inhibits GnRH- but not LH-induced meiosis in follicle-enclosed rat oocytes in vitro.
Previous studies have shown that gonadotrophin-releasing hormone (GnRH) can induce resumption of meiosis in follicle-enclosed rat oocytes. In the present study a GnRH antagonistic analogue ([D-pGlul,D-Phe2,-D-Trp3,6]LRF) was found to effectively abolish the stimulatory effect of a GnRH agonist upon resumption of meiosis and lactate accumulation in isolated pre-ovulatory rat follicles but the have no effect on LH stimulation of these parameters. It is concluded that although LH and GnRH can evoke a similar response they act through separate receptor sites and that it is unlikely that GnRH mediates the effect of LH on meiosis or glycolysis.
D000818:Animals; D002452:Cell Count; D005260:Female; D007773:Lactates / Q000378:metabolism; D007986:Luteinizing Hormone / Q000494:pharmacology*; D008540:Meiosis / Q000187:drug effects*; D009865:Oocytes / Q000187:drug effects* / Q000378:metabolism; D006080:Ovarian Follicle / Q000187:drug effects / Q000378:metabolism; D010063:Ovum / Q000187:drug effects*; D010906:Pituitary Hormone-Releasing Hormones / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D007773:Lactates; D010906:Pituitary Hormone-Releasing Hormones; D007986:Luteinizing Hormone