Neurochemical alterations produced by daily nicotine exposure in periadolescent vs. adult male rats

• Published in: European journal of pharmacology Vol. 502; no. 1; pp. 75 - 85
• Main Authors: Collins, Stephanie L., Wade, Dean, Ledon, Jennifer, Izenwasser, Sari
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 11.10.2004; Elsevier
• Subjects: Adolescence; Aging - drug effects; Aging - physiology; Animals; Autoradiography; Biological and medical sciences; Caudate Nucleus - chemistry; Caudate Nucleus - drug effects; Caudate Nucleus - metabolism; Dopamine; Dopamine Plasma Membrane Transport Proteins; Drug Administration Schedule; Male; Medical sciences; Membrane Glycoproteins - metabolism; Membrane Transport Proteins - metabolism; Nerve Tissue Proteins - metabolism; Nicotine; Nicotine - administration & dosage; Nucleus Accumbens - chemistry; Nucleus Accumbens - drug effects; Nucleus Accumbens - metabolism; Pharmacology. Drug treatments; Protein Binding - drug effects; Protein Binding - physiology; Putamen - chemistry; Putamen - drug effects; Putamen - metabolism; Rats; Rats, Sprague-Dawley; Receptors, Dopamine - metabolism; Serotonin; Serotonin Plasma Membrane Transport Proteins; Adolescence; Autoradiography; Dopamine; Serotonin; Nicotine; Alkaloid; Adult animal; Neurotransmitter; Male; Catecholamine
• ISSN: 0014-2999; 1879-0712
• DOI: 10.1016/j.ejphar.2004.08.039

Chronic treatment with nicotine differentially alters behavior in adolescent rats compared to adult rats. It is not known, however, whether the effects of nicotine on the neurochemical pathways with which it interacts differ in adolescents vs. adults. In the current study, the effects of a 7-day treatment with nicotine on nicotinic, dopaminergic, and serotonergic neurochemistry were examined in the caudate putamen and nucleus accumbens in periadolescent vs. adult male rats. Nicotine treatment increased dopamine transporter densities and decreased serotonin transporter densities in periadolescent rats. There was no change in nicotinic acetylcholine receptor densities or dopamine D1 or D2 receptor densities in nicotine-pretreated periadolescent rats. In adult rats pretreated with nicotine, there was an increase in nicotinic acetylcholine densities, but no change in dopamine transporter, dopamine D1 or D2 receptor, or serotonin transporter densities. Overall, these findings show that periadolescent rats have neurochemical adaptations to nicotine different from adult rats. These alterations may explain, at least in part, the differential behavioral effects of chronic nicotine in adult and adolescent male rats.