Effects of acute and chronic nicotine on somatodendritic dopamine release of the rat ventral tegmental area: in vivo microdialysis study.
The objectives of the present study were to examine the effects of acute and chronic nicotine on dopamine (DA) release in the ventral tegmental area (VTA) of Long-Evans rats using in vivo microdialysis. Systemic application of acute nicotine (0.1-0.3 mg/kg, s.c.) significantly increased (145% of baseline) DA release in the VTA. Chronic exposure to nicotine (0.3 mg/kg, s.c.) for 5 days followed by a challenge dose of nicotine (0.3 mg/kg, s.c.) also produced significant enhancement (136% of baseline) of DA release in the VTA. The results suggest that both acute and chronic nicotine treatment exert stimulatory effects on somatodendritic DA release in the VTA. The enhancement of DA release to subsequent challenge nicotine may be susceptible to mild desensitization.
Rahman
S
S
Smoking and Nicotine Dependence Research, Centre for Addiction and Mental Health, Toronto, Ontario, Canada. shafiq_rahman@camh.net
Zhang
J
J
Corrigall
W A
WA
D000818:Animals; D003712:Dendrites / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D008297:Male; D017551:Microdialysis; D009538:Nicotine / Q000494:pharmacology*; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000378:metabolism; D014029:Tobacco Use Disorder / Q000378:metabolism* / Q000503:physiopathology; D017557:Ventral Tegmental Area / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D011978:Receptors, Nicotinic; D009538:Nicotine; D004298:Dopamine