title: Effects of carbon monoxide in combination with behaviorally active drugs on fixed-ratio performance in the mouse.
abstract: The effects of carbon monoxide (3.75, 7.5, 15 and 30 ml/kg, IP) alone and in combination with ethanol (1.1 g/kg), nicotine (1.1 mg/kg), caffeine (36.1 mg/kg), chlorpromazine (2.2 mg/kg), diazepam (10 mg/kg), pentobarbital (23.1 mg/kg), d-amphetamine (1.4 mg/kg) or morphine (13.3 mg/kg) were evaluated in mice. Animals were trained to lever press under a fixed-ratio 32 schedule of water reinforcement. Response rates following CO-drug combinations were compared with the expected additive effects determined by the sum of the effects of each agent administered alone. CO (15 and 30 ml/kg) in combination with ethanol produced supra-additive effects. CO-chlorpromazine and CO-d-amphetamine combinations often produced greater than additive response-rate suppression, although differences from additivity did not reach statistical significance. The effects on response rates following CO in combination with nicotine, caffeine, diazepam, pentobarbital, or morphine were additive. These results suggest that concurrent use of therapeutic or abused drugs and CO exposure may place an individual at higher risk for behavioral toxicity.
authors.affiliation: Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0613.
authors.forename: J S
authors.initials: JS
authors.lastname: Knisely
authors.forename: D C
authors.initials: DC
authors.lastname: Rees
authors.forename: R L
authors.initials: RL
authors.lastname: Balster
mesh_terms: D000818:Animals; D002248:Carbon Monoxide / Q000008:administration & dosage / Q000633:toxicity*; D002491:Central Nervous System Agents / Q000494:pharmacology; D002492:Central Nervous System Depressants / Q000494:pharmacology; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D000431:Ethanol / Q000494:pharmacology; D008297:Male; D051379:Mice; D009538:Nicotine / Q000494:pharmacology; D012055:Reinforcement Schedule
chemical_list: D002491:Central Nervous System Agents; D002492:Central Nervous System Depressants; D000431:Ethanol; D009538:Nicotine; D002248:Carbon Monoxide