title: Caffeine and amphetamine produce cross-sensitization to nicotine-induced locomotor activity in mice.
abstract: Sensitization development is linked to the addictive potential of the drugs. The same mechanisms might play a role in sensitization development to the different addictive drugs. The aim of the study was to investigate the development of cross-sensitization to caffeine and amphetamine in nicotine-induced locomotor sensitization in mice. Caffeine (2.5-20 mg/kg), amphetamine (1-16 mg/kg) or saline were injected to Swiss-Webster mice and locomotor activity was recorded for 30 min. Nicotine (0.5-2 mg/kg) or saline were injected to mice and locomotor activity was recorded for 30 min. Process was applied for 19 days, every other day (10 sessions). Caffeine (5 mg/kg), amphetamine (4 mg/kg) or saline were challenged to the different groups of nicotine-sensitized mice 2 days later on the last nicotine injection, and locomotor activity was recorded. Repetitive injections of nicotine (0.5-2 mg) produced locomotor sensitization in mice. After caffeine and amphetamine challenge injections, locomotor activity of the nicotine-sensitized mice was found to be significantly higher than saline-pretreated mice. Saline challenge did not produce any significant effect in nicotine- or saline-pretreated mice. Our results suggest that a cross-sensitization developed to both caffeine and amphetamine in nicotine-sensitized mice. In conclusion, similar central mechanisms may be responsible for the development of addiction to these substances.
authors.affiliation: Hacettepe University, Specialization Area of Experimental Psychology, Ankara, Turkey.
authors.forename: Eylem
authors.initials: E
authors.lastname: Celik
authors.forename: I Tayfun
authors.initials: IT
authors.lastname: Uzbay
authors.forename: Sirel
authors.initials: S
authors.lastname: Karakas
mesh_terms: D000661:Amphetamine / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D051379:Mice; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D011897:Random Allocation
chemical_list: D000697:Central Nervous System Stimulants; D018722:Nicotinic Agonists; D002110:Caffeine; D009538:Nicotine; D000661:Amphetamine