Alpha-actin and cytochrome c mRNAs in atrophied adult rat skeletal muscle.
Specific complementary DNA (cDNA) hybridization probes were used to estimate the levels of alpha-actin and cytochrome c mRNAs and also 18S rRNA in three models of skeletal muscle atrophy. After 7 days of hindlimb suspension, or immobilization, or denervation, protein content decreased 26-32% in all muscles studied except suspended fast-twitch muscle, which lost only half as much protein. alpha-Actin mRNA content decreased 51-66% and cytochrome c mRNA content decreased 42-61% in slow- and fast-twitch muscles in all three models of atrophy. However, total RNA content did not show similar directional changes; RNA content decreased 27-44% in suspended and immobilized muscle but was unchanged in denervated fast-twitch muscle. The results were interpreted to suggest that loss of weight-bearing function of skeletal muscle is a major factor affecting the levels of alpha-actin and cytochrome c mRNAs during muscle atrophy.
Babij
P
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Department of Physiology and Cell Biology, Medical School, University of Texas Health Science Center, Houston 77225.
Booth
F W
FW
D000199:Actins / Q000235:genetics*; D000818:Animals; D003574:Cytochrome c Group / Q000235:genetics*; D003714:Denervation; D005260:Female; D006614:Hindlimb; D009132:Muscles / Q000201:enzymology* / Q000294:innervation; D009133:Muscular Atrophy / Q000201:enzymology*; D012333:RNA, Messenger / Q000032:analysis*; D012337:RNA, Ribosomal, 18S / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains
D000199:Actins; D003574:Cytochrome c Group; D012333:RNA, Messenger; D012337:RNA, Ribosomal, 18S