Alcohol and nicotine administration inhibits serotonin synthesis and tryptophan hydroxylase expression in dorsal and median raphe of young rats.
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 were reduced by alcohol and nicotine treatment in a dose-dependent manner. 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.
Jang
Mi-Hyeon
MH
Department of Physiology, College of Medicine, Kyung Hee University, #1 Hoigi-dong, Dongdaemoon-gu, Seoul 130-701, South Korea.
Shin
Min-Chul
MC
Lee
Taeck-Hyun
TH
Kim
Young-Pyo
YP
Jung
Sae-Bin
SB
Shin
Dong-Hoon
DH
Kim
Hong
H
Kim
Sung-Soo
SS
Kim
Ee-Hwa
EH
Kim
Chang-Ju
CJ
D000375:Aging / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000008:administration & dosage*; D000431:Ethanol / Q000008:administration & dosage*; D007274:Injections, Intraperitoneal; D008297:Male; D009538:Nicotine / Q000008:administration & dosage*; D011903:Raphe Nuclei / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000096:biosynthesis*; D012702:Serotonin Antagonists / Q000008:administration & dosage*; D014365:Tryptophan Hydroxylase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis*
D004791:Enzyme Inhibitors; D012702:Serotonin Antagonists; D012701:Serotonin; D000431:Ethanol; D009538:Nicotine; D014365:Tryptophan Hydroxylase