Inhibition of tachykinin release from peripheral endings of sensory nerves by nociceptin, a novel opioid peptide.
The novel heptadecapeptide opioid, nociceptin, produced a concentration-dependent (EC50 28 nM) suppression of the inotropic response of the guinea-pig isolated renal pelvis to electrical stimulation, a response mediated by release of tachykinins from sensory nerves. Nociceptin did not affect the response to neurokinin A, indicating a prejunctional site of action on tachykininergic nerves. The effect of nociceptin was unchanged in the presence of the mu, delta and kappa opioid receptor antagonists, naloxone, naltrindole and nor-binaltorphimine.
Giuliani
S
S
Pharmacology Department, Menarini Ricerche, Florence, Italy.
Maggi
C A
CA
D000818:Animals; D004558:Electric Stimulation; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007682:Kidney Pelvis / Q000187:drug effects; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009292:Narcotic Antagonists / Q000494:pharmacology; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism*; D015288:Neurokinin A / Q000494:pharmacology; D009475:Neurons, Afferent / Q000378:metabolism*; D018847:Opioid Peptides / Q000494:pharmacology*; D010525:Peripheral Nerves / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011957:Receptors, Opioid / Q000819:agonists*; D015320:Tachykinins / Q000378:metabolism*; D000097629:Nociceptin
D009292:Narcotic Antagonists; D015288:Neurokinin A; D018847:Opioid Peptides; D011957:Receptors, Opioid; D015320:Tachykinins; D000097629:Nociceptin