Effect of ethanol on rat brain protein synthesis. I. Acute administration.

The addition of ethanol to cell free protein synthesizing systems from the rat brain in vitro did not influence the incorporation of labeled amino acids into acid precipitable protein within a concentration range up to 10 mM. But in vivo acute administration of the drug to naive animals induced an activation of protein synthesis by cytoplasmic ribosomes isolated from the cerebral cortex and cerebellum. By contrast, incorporation of amino acids into mitochondrial or synaptosomal protein remained unchanged. The stimulating effect of ethanol on brain protein synthesis was connected with increased charging levels of brain transfer ribonucleic acids, which were initially confined to leucyl-tRNA. The activated agent was bound to the soluble enzyme fractions used in the cell-free systems.