Divergent effects of exercise on metabolic and mitogenic signaling pathways in XXXX skeletal muscle.

@entity1 @entity33644 @entity3963 @entity584 @entity25449 @entity10366 @entity669 @entity1366 @entity413
The molecular signaling mechanisms by which muscle contractions lead to changes in @entity413 metabolism and gene expression remain largely undefined. We assessed whether exercise activates MAP kinase proteins ( @entity1366 , @entity33644 , and @entity3963 MAP kinase) as well as @entity584 and @entity25449 in skeletal muscle from healthy volunteers obtained during and after one-leg cycle ergometry at approximately 70% VO2max. Exercise led to a marked increase in @entity1366 phosphorylation, which rapidly decreased to resting levels upon recovery. Exercise increased phosphorylation of @entity33644 and @entity3963 MAP kinase to a lesser extent than @entity1366 . In contrast to @entity1366 , @entity3963 MAP kinase phosphorylation was increased in nonexercised muscle upon cessation of exercise. Phosphorylation of the transcription factor @entity10366 was increased in nonexercised muscle upon cessation of exercise. Exercise did not activate @entity584 or increase @entity669 phosphorylation of @entity25449 . Thus, exercise has divergent effects on parallel MAP kinase pathways, of which only @entity3963 demonstrated a systemic response. However, our data do not support a role of @entity584 or @entity25449 in exercise/contraction-induced signaling in @entity1 skeletal. Activation of the different MAP kinase pathways by physical exercise appears to be important in the regulation of transcriptional events in skeletal muscle.
