Experimental alcoholic skeletal muscle myopathy is characterised by a rapid and sustained decrease in muscle RNA content. An investigation was made into the effects of ethanol feeding (36% of total calories) on skeletal muscle. From 7 to 42 days, muscle weights and protein and DNA contents of alcohol-treated rats were significantly lower (10-23%) than pair-fed controls (with glucose as 36% of total calories). Ethanol feeding markedly reduced muscle RNA content by 22-34%, when compared to controls. Muscle RNA content of ethanol-fed rats at 7, 14, 28 and 42 days of treatment was significantly lower than initial values (i.e. at 3 days) by 22-38%. Thus, ethanol feeding caused an initial net loss and thereafter a reduction in the rate of accretion of RNA. The marked and sustained loss in the muscle protein synthetic apparatus may be a precipitating event in the development of experimental skeletal muscle myopathy. 