Inhibition by pentobarbitone and urethane of the in vitro response of the adenohypophysis to luteinising hormone-releasing hormone in male rats.
1 The effect of urethane (ethyl carbamate) and sodium pentobarbitone on the luteinising hormone-releasing hormone (LH-RH)-stimulated secretion of luteinising hormone (LH) was investigated with hemipituitaries obtained from male rats and incubated in vitro. 2 Urethane and pentobarbitone were added to the incubation medium to provide final concentrations of 2.2 mg or 4 micrograms/ml and 100 micrograms or 0.1 microgram/ml respectively. The high doses of these anaesthetics blocked the LH-RH stimulated secretion of LH. The low doses significantly reduced the amounts of LH released in response to LH-RH but did not block the response completely. 3 Both concentrations of urethane reduced the basal release of LH. 4 The inhibitory action of the anaesthetics was reversible. 5 The results indicate that the two anaesthetics most commonly used in neuroendocrine experiments have a significant inhibitory action on the release of LH from the adenohypophysis.
D000818:Animals; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D066298:In Vitro Techniques; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology*; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D013997:Time Factors; D014520:Urethane / Q000494:pharmacology*
D007987:Gonadotropin-Releasing Hormone; D014520:Urethane; D007986:Luteinizing Hormone; D010424:Pentobarbital