Effects of zinc deficiency on the oxidation of retinol and ethanol in rats.

The zinc metalloenzyme alcohol dehydrogenase was assayed in subcellular fractions of liver and retina from zinc-deficient and control rats using retinol and ethanol as substrates. When the zinc concentrations of these tissues were reduced because of feeding inadequate dietary zinc, alcohol dehydrogenase was significantly lowered, and the retinol-retinal as well as the ethanol-ethyladehyde conversion was significantly reduced. While in older rats no changes occurred in liver zinc and alcohol dehydrogenase, the retina was more sensitive to the lack of dietary zinc than the liver. Young rats nursed by zinc-deficient dams showed the most severe changes in both tissues. The data suggest that zinc deficiency affects the utilization of vitamin A as well as the catabolism of ethanol.