Chronic ethanol administration decreases fatty acyl-CoA desaturase activities in rat liver microsomes.
The delta 9-desaturase system in liver microsome from rats treated chronically with ethanol was studied. Stearoyl-CoA desaturase activity decreased by 80% and palmitoyl-CoA desaturase activity was not detectable in microsomes from ethanol-fed rats, while activities of electron transport components such as NADH-cytochrome c and NADH-ferricyanide reductases remained unchanged. However, chronic ethanol administration resulted in an adaptive induction of the activity of NADPH-cytochrome c reductase and the contents of cytochrome b5 and P-450. The activity of the terminal component (cyanide-sensitive factor; CSF) of the desaturase system was greatly depressed by ethanol treatment. The NADH/NAD ratio in microsomes of ethanol-fed rats increased over 2-fold. These results suggest that, during chronic ethanol ingestion, decreased activities of delta 9-desaturases are due mainly to a decreased content of the terminal component of the desaturase system.
D000818:Animals; D000431:Ethanol / Q000494:pharmacology*; D044943:Fatty Acid Desaturases / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology*; D009245:NADH Dehydrogenase / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism
D000431:Ethanol; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase; C022311:palmitoyl-CoA desaturase; D009247:NADH, NADPH Oxidoreductases; D009251:NADPH-Ferrihemoprotein Reductase; C014227:ferricyanide reductase; D009245:NADH Dehydrogenase