Ribosomal RNA activity and protein in skeletal muscles of chronic ethanol-fed rats.
The effect of prolonged ethanol exposure on ribosomal RNA activity and the content of RNA and protein in skeletal muscles of 15- and 22-25-month-old rats was evaluated. Experimental rats were fed a liquid diet containing 6.7% ethanol for 2, 4 and 6 months, and control rats were pair-fed an isocaloric diet. The in vivo incorporation of [3H]puromycin into nascent peptides on messenger RNA-ribosome complexes was determined to assess muscle ribosomal RNA activity. This activity was significantly reduced in extensor digitorum longus and soleus muscles of rats fed ethanol for 2 months. While the total RNA content of these muscles was unchanged after feeding ethanol for 2, 4 and 6 months, their messenger RNA content was decreased from 26-34%. The total protein content was reduced after ethanol was consumed for 6 months. Taken together, the results suggest that alterations in the transcriptional or posttranscriptional control of messenger RNA may contribute toward the development of alcoholic myopathy after prolonged ethanol consumption.
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Neuroscience Research Laboratory, Veterans Administration Hospital, Hines, IL 60141.
D000437:Alcoholism / Q000378:metabolism*; D000818:Animals; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism*; D011691:Puromycin / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344
D009124:Muscle Proteins; D012333:RNA, Messenger; D012335:RNA, Ribosomal; D000431:Ethanol; D011691:Puromycin