DEVELOPMENT OF TOLERANCE TO EFFECTS OF ETHANOL DEPENDS ON ITS CONCENTRATION IN STOMACH

Background: The problem of alcohol dependence, as well as the repercussion of alcohol consumption is one of the most dramatic and socially relevant problems for modern society. Aims: Studying the development of tolerance to anxiolytic, psycho stimulant and analgesic effects of ethanol upon repeated intragastric administration of ethanol in the samedose, but in various volumes. Methods: Male Wistar rats were treated with ethanol at the same dose (2 g/kg), but in various concentrations (40 ml/kg 5%, 15,5 ml/kg 13%, and 5 ml/kg 40% v/v). The level of anxiety and locomotor activity of animals were evaluated in the elevated plus maze. The analgesic effect of ethanol was studied in the hot plate test. Results: Intragastric administration of ethanol in a dose of 2 g/kg had the anxiolytic, psychostimulant, and analgesic effects. Tolerance to the psychostimulant and analgesic effects develops most rapidly after treatment with small amounts of high-concentration ethanol. By contrast, tolerance to an anxiolytic action was formed rapidly after administration of large amounts of low-concentration ethanol. Conclusions: 1. The development of tolerance to various effects of ethanol depends on its concentration and gastric distention with the administered volume. 2. The development of tolerance to various effects of ethanol depends differently on the volume and concentration. 3. These results support our hypothesis that tolerance to the effect of ethanol is mainly related to its influence on the activity of gastric receptors, which mediates a variety of changes in the central nervous mechanisms.