Cocaine increases 5-HT1B mRNA in rat nucleus accumbens shell neurons.
Serotonin 5-HT(1B) receptors modulate behavioral responses to cocaine, but the effects of cocaine on endogenous 5-HT(1B) receptor expression are not known. Therefore, we examined the effect of binge cocaine administration on 5-HT1B mRNA expression in rat brain. We found that chronic, but not acute, binge cocaine exposure increased 5-HT(1B) mRNA by approximately 80% in nucleus accumbens shell and dorsal striatum. Surprisingly, 5-HT(1B) mRNA was increased in nucleus accumbens shell after chronic vehicle treatment as well, but this effect was driven by animals that were housed with cocaine-treated animals. Thus, 5-HT(1B) mRNA is upregulated by repeated exposure to cocaine and perhaps by social stress as well; both of these factors are relevant to the risk for relapse in cocaine addiction.
Hoplight
B J
BJ
Departments of Psychiatry and Behavioral Sciences, Harborview Medical Center, University of Washington, Box 359911, 325 Ninth Avenue, Seattle, WA 98104-2499, USA.
Vincow
E S
ES
Neumaier
J F
JF
D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight; D003042:Cocaine / Q000494:pharmacology*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D004334:Drug Administration Schedule; D005786:Gene Expression Regulation / Q000187:drug effects; D017403:In Situ Hybridization / Q000379:methods; D008297:Male; D009474:Neurons / Q000187:drug effects*; D009714:Nucleus Accumbens / Q000166:cytology*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D044302:Receptor, Serotonin, 5-HT1B / Q000235:genetics* / Q000378:metabolism
D018765:Dopamine Uptake Inhibitors; D012333:RNA, Messenger; D044302:Receptor, Serotonin, 5-HT1B; D003042:Cocaine