RELATIVE AND COMBINED ROLES OF ETHANOL AND PROTEIN-MALNUTRITION ON MUSCLE ZINC, POTASSIUM, COPPER, IRON, AND MAGNESIUM

The aim of the present study is to analyse the relative and combined e ffects of ethanol and protein malnutrition on muscle zinc, copper, iro n, potassium, and magnesium in ethanol-fed rats. The study was perform ed in 32 animals divided into four groups, fed with the Lieber-DeCarli control, 36% ethanol, 2% protein, and 36% ethanol 2% protein containi ng diets, respectively. Right gastrocnemius muscle was removed 2 month s later, and was studied both chemically and histochemical-morphometri cally. Both muscle zinc and potassium, but not copper nor iron nor mag nesium, were significantly decreased in the protein-deprived, ethanol- fed animals, the main effect of these variations being attributable to ethanol rather than to protein deprivation. However, coexisting prote in deprivation aggravated the decrease in both muscle zinc and potassi um. Both muscle zinc and potassium were significantly related to serum albumin, weight loss, and type IIb fibre atrophy; and muscle zinc, in addition, to the decrease in type IIb fibre proportion. Therefore, a decrease in muscle content of both elements is related to histochemica l-morphometrical changes observed in alcoholic myopathy. In addition, both ethanol and protein deficiency exerted independent, highly signif icant effects both on type IIb fibre atrophy and proportion.