Role of @entity1920 -activated protein kinase in glycogen synthase activity and @entity413 utilization: insights from @entity1 with XXXX .

@entity1 @entity1425 @entity3156 @entity1920 @entity9847 @entity33725 @entity6625 @entity413
It has been suggested that @entity1920 -activated protein kinase ( @entity33725 ) is involved in the regulation of @entity413 and glycogen metabolism in skeletal muscle. We used @entity1 with chronic high muscle glycogen stores and deficient glycogenolysis ( @entity9847 ) as a model to address this issue. Six @entity9847 @entity1 were compared with control subjects during exercise. Muscle alpha2AMPK activity increased in @entity9847 @entity1 (from 1.3 +/- 0.2 to 1.9 +/- 0.2 pmol min(-1) mg(-1), P = 0.05) but not in control subjects (from 1.0 +/- 0.1 to 1.3 +/- 0.3 pmol min(-1) mg(-1)). Exercise-induced phosphorylation of the in vivo @entity33725 substrate @entity6625 carboxylase (ACCbeta; Ser(221)) was higher (P < 0.01) in @entity9847 @entity1 than in control subjects (18 +/- 3 vs. 10 +/- 1 arbitrary units). Exercise-induced whole-body @entity413 utilization was also higher in @entity9847 @entity1 than in control subjects (P < 0.05). No correlation between individual @entity33725 or ACCbeta values and @entity413 utilization was observed. @entity3156 ( @entity3156 ) activity was decreased in @entity9847 @entity1 from 11 +/- 1.3 to 5 +/- 1.2 % (P < 0.05) and increased in control subjects from 19 +/- 1.6 to 23 +/- 2.3 % (P < 0.05) in response to exercise. This was not associated with activity changes of @entity3156 kinase 3 or protein phosphatase 1, but the changes in @entity3156 activity could be due to changes in activity of @entity33725 or protein kinase A (PKA) as a negative correlation between either ACCbeta phosphorylation (Ser(221)) or plasma @entity1425 and @entity3156 activity was observed. These findings suggest that @entity3156 activity is increased by glycogen breakdown and decreased by @entity33725 and possibly PKA activation and that the resultant @entity3156 activity depends on the relative strengths of the various stimuli. Furthermore, @entity33725 may be involved in the regulation of @entity413 utilization during exercise in @entity1 , although the lack of correlation between individual @entity33725 activity or ACCbeta phosphorylation (Ser(221)) values and individual @entity413 utilization during exercise implies that @entity33725 may not be an essential regulator.
