title: Acute effect of ethanol on membranes of the endoplasmic reticulum and on protein synthesis in rat liver.
abstract: The acute effect of ethanol on the membranes of hepatic endoplasmic reticulum, on the in vitro protein-synthetic activities of hepatic free and membrane-bound polyribosomes and on the plasma proteins of rats fasted overnight was investigated. Ethanol (0.75 g/100 g body weight) was tube-fed as a 50% (v/v) solution in saline 3 hr before sacrifice. Hepatic endoplasmic reticulum membranes from control and ethanol-treated rats were compared using the following techniques: (1) lactoperoxidase-catalyzed radioiodination of proteins and sodium dodecylsulfate-polyacrylamide gel electrophoresis, and (2) measurement of 14C-choline incorporation into membranes. Hepatic microsomal membranes from ethanol-treated rats incorporated in vitro les 125I into total proteins (as well as into the 55,000 molecular weight proteins) and incorporated in vivo less 14C-choline into microsomal membranes than membranes of control rats. Ethanol administration inhibited in vivo incorporation of 14C-leucine or 14C-phenylalanine into liver protein and plasma albumin and globulin. The data also indicate that an acute dose of ethanol reduced the in vitro protein-synthetic activity of hepatic membrane-bound polyribosomes, while free polyribosomes were relatively unaffected.
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D007425:Intracellular Membranes / Q000187:drug effects; D007930:Leucine / Q000378:metabolism; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D010649:Phenylalanine / Q000378:metabolism; D014176:Protein Biosynthesis; D051381:Rats
chemical_list: D001798:Blood Proteins; D000431:Ethanol; D010649:Phenylalanine; D007930:Leucine; D002794:Choline