Cholecystokinin-A but not cholecystokinin-B receptor stimulation induces endogenous opioid-dependent antinociceptive effects in the hot plate test in mice.
The effects of intracerebroventricular administration of the cholecystokinin (CCK) analogue, BDNL, and the selective CCK-B agonist, BC 264, were determined using the hot plate test in mice. BDNL (0.2 nmol and 0.5 nmol) increased the jump and the paw lick latencies. These effects were blocked by the CCK-A antagonist MK-329 (0.02 mg/kg), supporting the involvement of CCK-A receptors in CCK-induced analgesia. In contrast, the selective CCK-B agonist BC 264 produced, at one dose (2.5 nmol), a slight decrease in the lick latency that was only antagonized by the CCK-B antagonist. Naloxone, but not naltrindole, antagonized BDNL-induced analgesia. The results suggest that activation of CCK-A receptors by BDNL leads to antinociceptive responses indirectly mediated by stimulation of mu-opioid receptors by endogenous enkephalins.
Derrien
M
M
Unité de Pharmacochimie Moléculaire et Structurale, U 266 INSERM-URA 1500 CNRS, Université René Descartes, UFR des Sciences Pharmaceutiques et Biologiques, Paris, France.
Noble
F
F
Maldonado
R
R
Roques
B P
BP
D000818:Animals; D001570:Benzodiazepinones / Q000008:administration & dosage / Q000494:pharmacology*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D002766:Cholecystokinin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D020109:Devazepide; D006358:Hot Temperature; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009270:Naloxone / Q000494:pharmacology; D010146:Pain / Q000503:physiopathology*; D010446:Peptide Fragments / Q000008:administration & dosage / Q000494:pharmacology; D010671:Phenylurea Compounds; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors / Q000502:physiology*; D012844:Sincalide / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology
C084553:BC 264; D001570:Benzodiazepinones; D010446:Peptide Fragments; D010671:Phenylurea Compounds; D011949:Receptors, Cholecystokinin; D009270:Naloxone; C058121:L 365260; D002766:Cholecystokinin; C047716:cholecystokinin (27-33), tert-butyloxycarbonyl-Nle(28,31)-; D020109:Devazepide; D012844:Sincalide