Differential modulation of mu- and delta-opioid antinociception by neuropeptide FF receptors in young mice.
The ability of neuropeptide FF (NPFF) to modulate mu- and delta-opioid-induced analgesia by intracerebroventricular administration was compared in adults and 14-day-old mice. In adults, opioid-induced analgesia was predominantly mediated by mu-receptors whereas mu- and delta-receptors were equally involved in pups. An NPFF analog, 1 DMe, reduced the analgesic effect of DAGO and [D.Ala2]deltorphin-I, mu and delta selective agonists respectively. However, a high dose of 1DMe (22 nmol) increased both morphine and [D.Ala2]deltorphin-I-induced analgesia. Dose-response curves for 1DMe in the presence of naltrindole or naltrexone, delta- and mu-opioid selective antagonists respectively, indicate that 1DMe preferentially reversed mu-receptor-mediated but increased delta-receptor-mediated analgesia. These findings demonstrate differences in control of mu- and delta-induced analgesia by NPFF receptors.
Desprat
C
C
Institut de Pharmacologie et de Biologie Structurale, CNRS, Toulouse, France.
Zajac
J M
JM
D000367:Age Factors; D000701:Analgesics, Opioid / Q000494:pharmacology; D000818:Animals; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009020:Morphine / Q000494:pharmacology; D009271:Naltrexone / Q000031:analogs & derivatives / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology; D009619:Nociceptors / Q000187:drug effects* / Q000502:physiology*; D009842:Oligopeptides / Q000494:pharmacology; D018013:Receptors, Neuropeptide / Q000378:metabolism*; D017465:Receptors, Opioid, delta / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017450:Receptors, Opioid, mu / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*
D000701:Analgesics, Opioid; D004745:Enkephalins; D009292:Narcotic Antagonists; D009479:Neuropeptides; D009842:Oligopeptides; D018013:Receptors, Neuropeptide; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu; C083929:neuropeptide FF receptor; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; C060208:deltorphin I, Ala(2)-; C080757:tyrosyl-leucyl-N-methylphenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide; D009271:Naltrexone; D009020:Morphine; C053651:phenylalanyl-leucyl-phenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide; C055382:naltrindole