title: Effects of chronic ethanol consumption on rat upper gastrointestinal system: functional and histologic findings.
abstract: The purpose of the present study was to determine the effect of chronic alcohol consumption on reactivity of esophageal tunica muscularis mucosae (TMM) and lower esophageal sphincter (LES) smooth muscle. Six male rats in alcohol-fed group received ethanol (7.2% v/v) in a modified liquid diet for 4 weeks. Two control groups were used; six rats in the standard diet-fed group received rat chow and water for 4 weeks. Six rats in sucrose-fed group were given sucrose and received a liquid diet. The smooth muscle reactivity of TMM and LES strips from ethanol-fed and control animals was evaluated in organ chambers. Also histologic study was undertaken to show effects of chronic alcohol consumption. Maximum contractile responses of TMM to KCl and carbachol were decreased in the ethanol-fed group compared to the control groups. Relaxant responses to serotonin were decreased in the ethanol-fed group compared to the control groups. In TMM, isoproterenol- and papaverine-induced relaxant responses were similar in the ethanol-fed and control groups. In LES smooth muscle, relaxant responses to papaverine or isoproterenol were similar in the control groups and the ethanol-fed group. There was no change in agonist potency among the groups. The relaxation response elicited by nicotine and sodium nitroprusside (SNP) or contractile response elicited by carbachol and 80 mM KCl was decreased with maximum responses and pD(2) values, in the ethanol-fed group compared to that of the control groups in LES. Decreased nNOS immunoreactivity in myenteric plexus was found in alcohol-exposed group compared to control groups. Our findings suggest that chronic alcohol consumption impairs relaxant and contractile responses of both TMM and LES smooth muscle and it may contribute to gastroesophageal reflux commonly seen after alcohol binges.
authors: Department of Histology and Embryology, Kocaeli University Medical School, Turkey.
authors: Yusufhan
authors: Y
authors: Yazir
authors: Melih
authors: M
authors: Tugay
authors: Zafer
authors: Z
authors: Utkan
authors: Tijen
authors: T
authors: Utkan
mesh_terms: D000428:Alcohol Drinking; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D049630:Esophageal Sphincter, Lower / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D004947:Esophagus / Q000187:drug effects* / Q000294:innervation / Q000473:pathology / Q000503:physiopathology; D000431:Ethanol / Q000097:blood / Q000633:toxicity*; D005769:Gastrointestinal Motility / Q000187:drug effects*; D007150:Immunohistochemistry; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects* / Q000294:innervation / Q000473:pathology / Q000503:physiopathology; D009197:Myenteric Plexus / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D009465:Neuromuscular Agents / Q000494:pharmacology; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D009465:Neuromuscular Agents; D000431:Ethanol; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat