Tyr-MIF-1 attenuates antinociceptive responses induced by three models of stress-analgesia.
Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2), a biologically active brain peptide, has previously been shown to antagonize the analgesia induced by morphine. In this report experiments are described in which mice were tested on the hot-plate in three models of antinociception - shock, novel environment, and warm-water swim - after the administration of various doses of Tyr-MIF-1 without any exogenous opiates. The peptide reduced the antinociception produced by all three methods of inducing endogenous antinociception. These results add further support for the existence of peptides like Tyr-MIF-1 that act as opiate antagonists.
D000698:Analgesia; D000700:Analgesics / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D009075:MSH Release-Inhibiting Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D051379:Mice; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D013312:Stress, Physiological
D000700:Analgesics; D009292:Narcotic Antagonists; D009270:Naloxone; C036930:tyrosyl-prolyl-leucyl-glycinamide; D009075:MSH Release-Inhibiting Hormone