Nicotine reinforcement in rats with histories of cocaine self-administration.
Few reports have described conditions under which nicotine self-administration occurs in rats. In this study, rats which initially lever pressed for cocaine infusion (0.05 mg/kg) during 1 h experimental sessions continued to obtain similar infusion numbers when nicotine (0.03 mg/kg) was available. When saline was substituted for nicotine, infusions decreased from 11.8 +/- 4.5/h to 5.4 +/- 1.1/h but returned to pre-saline levels when it was reintroduced (12.0 +/- 5.4/h). These results indicate that nicotine can serve as a positive reinforcer for rats under the historical and schedule conditions described.
Tessari
M
M
Glaxo Research Laboratories, Verona, Italy.
Valerio
E
E
Chiamulera
C
C
Beardsley
P M
PM
D000818:Animals; D003042:Cocaine / Q000494:pharmacology*; D008297:Male; D009538:Nicotine / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D012646:Self Administration; D012965:Sodium Chloride / Q000494:pharmacology
D012965:Sodium Chloride; D009538:Nicotine; D003042:Cocaine