Effects of Ethanol on the Motility of Isolated Strips of Antrum and Duodenum of the Rabbit / 대한마취과학회지

ABSTRACT

Alcohol beverages have been used since the dawm of history and the pharmacology of alcohol has been studied extensively and the question whether alcohol is a stimulant has long been debated. now there seems little couble that alcohol is a primarys and continuous depressant of the CNS, and the general pharmacologic action of alcohol on the body is one of depression. The effects of various concentrations and type of alcoholic beverages on the gastrointestinal motor and secretory functions are influenced by a number of factors such as the state by the digestive processes, the presence or absence or gastrointestinal diseases, the amount and type of food present, the degree of tolerance for alcohol, accompanying psychological factiors, and so forth. it is generally accepted that gastirc secretion is stimulated by ehanol, but effects of ethanol on the motility of the gastrointestinal tract has not been clarified yet. Hence the present study was undertaken to investigate the effects of ethanol on gastrointestinal motility. The rabbits of either sex, weighting about 2kg, were killed by air embolism after 72 hours deprivation of food except water. The stomach and duodenum were isolated and cut into two parts, i.e. antrum and duodenum. Each strip of antrum and duodenum, sized 0.5X2.0cm, was placed in temperature controlled uscle chamber(37 degrees C) Containing Tyrode's solution and its contractile movement was recorded on Grass Polygraph(Model 7) via force displacement transducer(FT.03). The results are summarized as follows 1) The strips of gastric antrum and duodenum showed spontaneous regular movement through the experimental period. Administration of ethanol from 0.1 to 1.0% inhibited the amplitude and frequency of both strips with dose-dependent manner. Most strips of the duodenum and 6 strips of the antrum showed relaxations of tone by ethanol and 4 strips of the antrum showed increased tone. 2) Tonic contraction of antral strips by ethanol was abolished only by the combined pretreatment of atropine and chlorpheniramine, or atropine and cimetidine, not by the phentolamine, proproanolol, atropine, hexamethonium, chlorpheniramine or cimetidine alone. 3) Inhibition of antral and duodenal motility by ethanol was not abolished by anyy one of the receptor blocking agents such as adrenergic alpha and beta, buscarinic, or histaminergic H-1 and H-2 receptor blocking agents. By the above resutls, it may be concluded that ethanol inhibits the motility of the duodenum, but excites or inhibits the motility of the gastric antrum. It is likely that the inhibitory effect of ethanol is it derect action on the smooth muscle, and the excitatory effect is mediated by a mechanism related with histamine and acetylcholine.