title: Protective effect of bupropion on morphine tolerance and dependence in mice.
abstract: Possible reversal of morphine-induced tolerance and dependence by bupropion was studied in mice. A 10-day repeated injection regimen was followed to induce morphine tolerance and dependence. Bupropion (2 and 5 mg/kg) per se, when chronically administered for 9 days, failed to produce any significant change in tail-flick latency compared with the control mice. Chronic administration of bupropion (2 or 5 mg/kg) during the induction phase (days 1-9) delayed the development of tolerance to the antinociceptive action of morphine and also reversed naloxone- (2 mg/kg) precipitated withdrawal jumps. On the other hand, acute administration of bupropion (2 or 5 mg/kg) on day 10, i.e., during the expression phase of morphine dependence, reduced the incidence of naloxone-precipitated withdrawal jumps without affecting tolerance to the analgesic effect. In conclusion, results of the present study suggest the potential use of bupropion in tolerance and dependence.
authors.affiliation: Pharmacology Division, University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India.
authors.forename: D
authors.initials: D
authors.lastname: Joshi
authors.forename: A
authors.initials: A
authors.lastname: Singh
authors.forename: P S
authors.initials: PS
authors.lastname: Naidu
authors.forename: S K
authors.initials: SK
authors.lastname: Kulkarni
mesh_terms: D000701:Analgesics, Opioid; D000818:Animals; D016642:Bupropion / Q000008:administration & dosage / Q000494:pharmacology*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D004338:Drug Combinations; D004347:Drug Interactions; D004361:Drug Tolerance; D005260:Female; D008297:Male; D051379:Mice; D009020:Morphine; D009021:Morphine Dependence / Q000209:etiology / Q000517:prevention & control*; D017288:Pain Threshold / Q000187:drug effects
chemical_list: D000701:Analgesics, Opioid; D018765:Dopamine Uptake Inhibitors; D004338:Drug Combinations; D016642:Bupropion; D009020:Morphine