title: Enhancement of the ambulation-increasing effect of opioid analgesics by ethanol in mice.
abstract: The interaction between opioid analgesics (morphine and buprenorphine) and central depressants (ethanol, pentobarbital and diazepam) was investigated by means of ambulatory activity in mice. The ambulation-increasing effect of both morphine (10 mg/kg, s.c.) and buprenorphine (1 mg/kg, s.c.) was enhanced by the combined administration of ethanol (0.8-3.2 g/kg, p.o.) in a dose-dependent manner. Naloxone (0.1 mg/kg, s.c.) was effective for reducing the enhanced ambulatory activity. The pretreatment with Ca-cyanamide (5 mg/kg, p.o., 30 min before) reduced the enhancement of the ambulation-increasing effect induced by the combined administration of opioid analgesics with ethanol, although it scarcely modified that of morphine and buprenorphine alone. On the other hand, neither pentobarbital (1-30 mg/kg, s.c.) nor diazepam (0.25-2 mg/kg, s.c.) modified markedly the ambulation-increasing effect of morphine and buprenorphine. The present results suggest that ethanol specifically interacted with opioid analgesics when the mouse's ambulatory activity was used as the indicator.
authors.affiliation: Division for Behavior Analysis, Gunma University School of Medicine, Maebashi, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kuribara
authors.forename: T
authors.initials: T
authors.lastname: Asashi
authors.forename: S
authors.initials: S
authors.lastname: Tadokoro
mesh_terms: D000818:Animals; D002047:Buprenorphine / Q000008:administration & dosage / Q000494:pharmacology*; D003484:Cyanamide / Q000494:pharmacology; D003975:Diazepam / Q000008:administration & dosage / Q000494:pharmacology; D004334:Drug Administration Schedule; D004347:Drug Interactions; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051379:Mice; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects*; D009270:Naloxone / Q000494:pharmacology; D010424:Pentobarbital / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D009270:Naloxone; D000431:Ethanol; D002047:Buprenorphine; D003484:Cyanamide; D009020:Morphine; D010424:Pentobarbital; D003975:Diazepam