Protein synthesis in mitochondrial and microsomal fractions from rat brain and liver after acute or chronic ethanol administration

Incorporation of C¹⁴ Leucine was determined in vitro or in vivo in isolated mitochondria and microsomes of rat brain and liver after acute or chronic ethanol administration in vivo. The protein synthesis in mitochondrial and microsomal preparation was inhibited respectively by chloramphenicol and cycloeximide, specific inhibitors for the two systems tested. The experimental data demonstrate that the in vitro protein synthesis in both systems, mitochondrial and microsomal, is strongly affected only after chronic treatment which produces significant activation at the mitochondrial and microsomal level in the liver and an inhibition on the same systems of the brain. The data for in vivo protein synthesis instead show strong inhibition after acute administration, except for brain mitochondria, which are practically unaffected, while after chronic treatment no significant alterations are observed.