CHRONIC ETHANOL ADMINISTRATION ENHANCES RETINOIC ACID AND TRIIODOTHYRONINE RECEPTOR EXPRESSION IN MOUSE-LIVER

Chronic alcoholism induces perturbations of storage and metabolization of retinol and related compounds. After 6 months of ethanol consumpti on we have observed in mouse liver an increased expression of Tri-iodo thyronine receptors (TR) while the expression of retinoic acid (RA) re ceptors (RAR) was unaffected. After 10 months of alcoholization the TR expression was strongly increased and the RAR expression was also inc reased. At this time the activity of aldehyde dehydrogenase and that o f alcohol dehydrogenase, two enzymes involved in biosynthesis of RA fr om retinol, were similar in the liver of alcoholized and pair-fed mice . Thus it can be hypothesized that (i) the change of RAR expression wa s, at least in part, the result of a change of TR expression (result i n agreement with previous data), (ii) the increased expression of RAR could induce apoptosis and subsequently liver necrosis.