Epinephrine upregulates calpain activity in cultured C2C12 muscle cells.
C2C12 cells were grown to confluence at 37 degrees C under a continuous 5% CO(2) stream and myotube formation was stimulated. The cultures were then incubated with or without 2 microg/mL epinephrine for 18 h prior to harvesting and calpain extraction. Epinephrine treatment resulted in a three-fold increase in extractable mu-calpain activity (P < 0.05), a three-fold increase in extractable m-calpain activity (P < 0.05), a 36% increase in calpastatin activity (P < 0.001), and a 16% decrease (P < 0.05) in the total protein content in the C2C12 cell homogenate. These results suggest that calpains may play a role in protein metabolism and that the hormone epinephrine may be directly involved in the regulation of their cellular expression.
Ertbjerg
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P
Department of Dairy and Food Science, The Royal Veterinary and Agricultural University, Frederiksberg, Denmark. peer@kvl.dk
Lawson
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MA
Purslow
P P
PP
D000818:Animals; D002154:Calpain / Q000378:metabolism*; D002460:Cell Line; D004837:Epinephrine / Q000494:pharmacology*; D051379:Mice; D009132:Muscles / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013552:Swine; D015854:Up-Regulation / Q000187:drug effects*
D002154:Calpain; D004837:Epinephrine