THE effects of acute in vivo (−)-nicotine exposure on neuronal expression of mRNA encoding the vesicular acetylcholine transport (VAChT) and the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (G3PDH) were examined. The reverse transcription polymerase chain reaction was used to amplify cDNA derived from brain tissue of adult male rats injected acutely with (−)-nicotine and semi-quantification of cDNA products conducted using anion exchange chromatography. In cerebral cortex, levels of cDNA derived from the VAChT mRNA were increased by > 65% above control levels 1 h after (−)-nicotine (0.8 mg/kg, s.c.) exposure. In hippocampal samples, levels of this cDNA were increased by 15% above control levels. cDNA derived from G3PDH mRNA was increased by 86% and 280% above control levels in the cerebral cortex and hippo-campus, respectively. Thus, increased expression and function of proteins associated with these mRNA species are likely consequences of acute (−)-nicotine exposure.