Interaction of liver arginase and L-arginine-NO system in the processes of detoxification, lipid peroxidation and the formation of the thyroid status in rats with chronic ethanol intoxication

Abstract

A sufficient number of facts testifying the importance of liver arginase and nitrogen monoxide in the life processes in the normal and pathological conditions have been accumulated to date. The aim of the study was to determine the significance of the relationship and interaction of liver arginase and L-arginine-NO system in the processes of detoxification, lipid peroxidation and the formation of the thyroid status in rats with chronic ethanol intoxication. In rat experiments using the modern physiological, biochemical research methods and a pharmacological approach, it was found that chronic ethanol intoxication leads to a decrease in the liver arginase activity and the triiodothyronine concentration. At the same time, the increase in the level of “average molecules”, NO3 – /NO2 –, the content of lipid peroxidation products in the plasma, as well as the increase in the blood toxicity degree, the activity of alanine amino transferase, aspartate amino transferase and the narcotic sleep duration were observed. Hyperthyroid rats demonstrated the increased liver arginase activity, the processes of detoxification, lipid peroxidation and body temperature while rats with the experimental hypothyroidism showed the opposite results. The liver arginase depression caused by the injection of Nω-hydroxy-nor-L-arginine (Nor-NOHA), or L-valine into the body prevents the body temperature increase and the development of characteristic changes in the detoxification and lipid peroxidation processes acted upon by exogenous triiodothyronine. Under the conditions of the liver arginase inhibition by Nor-NOHA or L-valine, the ethanol action is accompanied by a more significant inhibition of the liver detoxification function and an increase of NO3 – /NO2 – levels in blood plasma. The preliminary injection of an NG-nitro-L-arginine methyl ester inhibitor of NO-synthase into the animal’s body weakensthe toxic ethanol effect on the liver, as well asthe development of characteristic changes in the liver arginase activity, in the processes of detoxification and lipid peroxidation in rats with chronic ethanol intoxication. Apparently, the activity of liver arginase and L-arginine-NO system determines the severity of detoxification, lipid peroxidation processes and the formation of the thyroid status in the conditions of chronic alcoholization, which is important in the ethanol intoxication pathogenesis.