Antinociceptive effects of thyrotrophin-releasing hormone and its analogues in the rat periaqueductal grey region.
Thyrotrophin-releasing hormone (TRH) and its analogues were injected into the periaqueductal grey (PAG) area of brain in conscious rats and the response time (tail-flick) to a thermal stimulus was recorded. TRH and some of the analogues had an antinociceptive action which, in the case of TRH, was prevented by naltrexone. TRH may interact with endogenous opioid systems in the PAG.
D000700:Analgesics; D000818:Animals; D009271:Naltrexone / Q000494:pharmacology; D010146:Pain / Q000517:prevention & control*; D010487:Periaqueductal Gray / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000187:drug effects; D013973:Thyrotropin-Releasing Hormone / Q000037:antagonists & inhibitors / Q000494:pharmacology* / Q000627:therapeutic use
D000700:Analgesics; D009271:Naltrexone; D013973:Thyrotropin-Releasing Hormone