Korean J Physiol Pharmacol.  2003 Feb;7(1):5-8.

Acute Effect of Alcohol and Nicotine on 5-Hydroxytryptamine Synthesis and Tryptophan Hydroxylase Expression in Dorsal and Median Raphe of Rats

• Jang MH
• Shin MC
• Chang HK
• Lee TH
• Kim KH
• Kim YJ
• Kim CJ

Abstract

Alcohol abuse and cigarette smoking have been on the rise worldwide and it has been reported that alcohol and nicotine influence serotonergic neuronal activity in the dorsal raphe. Serotonin (5-hydroxytryptamine, 5-HT) has been implicated in the pathophysiology of various neuropsychiatric disorders. In the present study, the effects of alcohol and nicotine on the synthesis of 5-HT and the expression of tryptophan hydroxylase (TPH), the rate limiting enzyme of 5-HT synthesis, in the dorsal and median raphe of young rats were investigated via immunohistochemistry. The numbers of the 5-HT-positive and TPH-positive cells in raphe nuclei were reduced by alcohol and nicotine treatment, and these numbers were reduced more potently by co-administration of alcohol and nicotine. Based on the results, it can be suggested that the pathogenesis of alcohol- and nicotine-induced neuropsychological disorders involves alcohol- and nicotine-induced suppression of 5-HT synthesis and TPH expression in raphe, and that this may be of particular relevance in the consumption of alcohol and nicotine during adolescence.

Keyword

Alcohol; Nicotine; 5-Hydroxytryptamine; Tryptophan hydroxylase; Dorsal raphe nuclei; Median raphe nuclei; Adolescence

MeSH Terms

Adolescent
Alcoholism
Animals
Humans
Immunohistochemistry
Nicotine*
Raphe Nuclei
Rats*
Serotonergic Neurons
Serotonin*
Smoking
Tryptophan Hydroxylase*
Tryptophan*
Nicotine
Serotonin
Tryptophan
Tryptophan Hydroxylase