In Vitro and In Situ Skeletal Muscle Pyruvate Dehydrogenase Activity in Adrenalectomized and Glucocorticoid Treated Rats

1984 ◽  
Vol 16 (10) ◽  
pp. 529-531 ◽  
Author(s):  
M. E. C. Förster ◽  
P. Schadewaldt ◽  
M. Schwenen ◽  
W. Staib
Keyword(s):  
Skeletal Muscle ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase

scholarly journals Glucose metabolism in perfused skeletal muscle. Pyruvate dehydrogenase activity in starvation, diabetes and exercise

1976 ◽  
Vol 158 (2) ◽  
pp. 203-210 ◽  
Author(s):  
S A Hagg ◽  
S I Taylor ◽  
N B Ruberman
Keyword(s):  
Skeletal Muscle ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Preceding Paper ◽  
Diabetic Rats ◽  
Pyruvate Dehydrogenase Kinase ◽  
Lactate Oxidation ◽  
Pyruvate Oxidation ◽  
Measured Activity ◽  
Exercise Induced

1. The interconversion of pyruvate dehydrogenase between its inactive phosphorylated and active dephosphorylated forms was studied in skeletal muscle. 2. Exercise, induced by electrical stimulation of the sciatic nerve (5/s), increased the measured activity of (active) pyruvate dehydrogenase threefold in intact anaesthetized rated within 2 min. No further increase was seen after 15 min of stimulation. 3. In the perfused rat hindquarter, (active) pyruvate dehydrogenase activity was decreased by 50% in muscle of starved and diabetic rats. Exercise produced a twofold increase in its activity in all groups; however, the relative differences between fed, starved and diabetic groups persisted. 4. Perfusion of muslce with acetoacetate (2 mM) decreased (active) pyruvate dehydrogenase activity by 50% at rest but not during exercise. 5. Whole-tissue concentrations of pyruvate and citrate, inhibitors of (active) pyruvate dehydrogenase kinase and (inactive) pyruvate dehydrogenase phosphate phosphatase respectively, were not altered by excerise. A decrease in the ATP/ADP ratio was observed, but did not appear to be sufficient to account for the increase in (active) pyruvate dehydrogenase activity. 6. The results suggest that interconversion of the phosphorylated and dephosphorylated forms of pyruvate dehydrogenase plays a major role in the regulation of pyruvate oxidation by eomparison of enzyme activity with measurements of lactate oxidation in the perfused hindquarter [see the preceding paper, Berger et al. (1976)] suggest that pyruvate oxidation is also modulated by the concentrations of substrates, cofactors and inhibitors of (active) pyruvate dehydrogenase activity.

Enhanced skeletal muscle arteriolar reactivity to ANG II after recovery from ischemic acute renal failure

2005 ◽  
Vol 289 (6) ◽  
pp. R1770-R1776 ◽  
Author(s):  
David P. Basile ◽  
Deborah L. Donohoe ◽  
Shane A. Phillips ◽  
Jefferson C. Frisbee
Keyword(s):  
Skeletal Muscle ◽  
Renal Failure ◽  
Acute Renal Failure ◽  
Pressor Response ◽  
Gracilis Muscle ◽  
Ang Ii ◽  
Sprague Dawley

In addition to the long-term renal complications, previous studies suggested that after acute renal failure (ARF), rats manifest an increased pressor response to an overnight infusion of ANG II. The present study tested whether recovery from ARF results in alterations in sensitivity to the peripheral vasculature. ARF was induced in Sprague-Dawley rats by 45 min of bilateral renal ischemia and reperfusion. Animals were allowed to recover renal structure and function for 5–8 wk, after which the acute pressor responses to ANG II were evaluated either in vivo in in situ skeletal muscle arterioles or in isolated gracilis muscle arteries in vitro. Baseline arterial pressure was not different in ARF rats vs. sham-operated controls, although ARF rats exhibited an enhanced pressor response to bolus ANG II infusion compared with control rats. Steady-state plasma ANG II concentration and plasma renin activity were similar between ARF and control rats. Constrictor reactivity of in situ cremasteric arterioles from ARF rats was enhanced in response to increasing concentrations of ANG II; however, no difference was observed in arteriolar responses to elevated Po2, norepinephrine, acetylcholine, or sodium nitroprusside. Isolated gracilis muscle arteries from ARF rats also showed increased vasoconstriction in response to ANG II but not norepinephrine. In conclusion, recovery from ischemic ARF is not associated with hypertension but is associated with increased arteriolar constrictor reactivity to ANG II. Although the mechanisms of this altered responsiveness are unclear, such changes may relate, in part, to cardiovascular complications in patients with ARF and/or after renal transplant.

Characterization of distinct mesenchymal-like cell populations from human skeletal muscle in situ and in vitro

2010 ◽  
Vol 316 (15) ◽  
pp. 2513-2526 ◽  
Author(s):  
Séverine Lecourt ◽  
Jean-Pierre Marolleau ◽  
Olivia Fromigué ◽  
Karine Vauchez ◽  
Rina Andriamanalijaona ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Human Skeletal Muscle ◽  
Cell Populations

Stimulation of Pyruvate Dehydrogenase Activity in Intact Rat Adipocytes by Insulin Mediator from Rat Skeletal Muscle*

Endocrinology ◽  
1985 ◽  
Vol 116 (3) ◽  
pp. 1011-1016 ◽  
Author(s):  
LEONARD JARETT ◽  
ELLEN H. A. WONG ◽  
JUDITH A. SMITH ◽  
S. LANCE MACAULAY
Keyword(s):  
Skeletal Muscle ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Rat Skeletal Muscle ◽  
Rat Adipocytes ◽  
Stimulation Of

Skeletal muscle pyruvate dehydrogenase activity during acetate infusion in humans

1995 ◽  
Vol 268 (5) ◽  
pp. E1007-E1017 ◽  
Author(s):  
C. T. Putman ◽  
L. L. Spriet ◽  
E. Hultman ◽  
D. J. Dyck ◽  
G. J. Heigenhauser
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acid ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Acetate Metabolism ◽  
Acetyl Coa ◽  
Acid Cycle ◽  
Citrate Accumulation ◽  
Acetyl Group ◽  
Glucose Fatty Acid Cycle

Pyruvate dehydrogenase activity (PDHa), acetyl group, and citrate accumulation were examined in human skeletal muscle at rest and during cycling exercise while acetate was infused. Eight subjects received 400 mmol of sodium acetate (Ace) at a constant rate during 20 min of rest, 5 min of cycling at 40% maximal O2 uptake (VO2max) and 15 min of cycling at 80% VO2max. Two weeks later experiments were repeated while 400 mmol of sodium bicarbonate was infused in the control condition (CON). Ace infusion increased muscle acetyl-coenzyme A (acetyl-CoA), citrate, and acetylcarnitine. A decline in resting PDHa during 20 min of Ace infusion (0.37 +/- 0.08 vs. 0.16 +/- 0.03 mmol.min-1.kg wet wt-1) coincided with an elevation in the acetyl-CoA-to-free CoA ratio (acetyl-CoA/CoASH; 0.28 +/- 0.04 to 0.73 +/- 0.14). After 20 min of CON infusion, resting PDHa (0.32 +/- 0.06 mmol.min-1.kg wet wt-1) was similar to PDHa before Ace infusion. During exercise, acetyl-CoA, citrate, and acetyl-CoA/CoASH were further elevated, and the differences that existed at rest were resolved. PDHa increased to the same extent in Ace and CON, in which it was 44-47% transformed after 5 min at 40% VO2max and completely transformed after 15 min at 80% VO2max. At rest PDHa was regulated by variations in acetyl-CoA/CoASH secondary to enhanced acetate metabolism. Conversely, during exercise PDHa regulation appeared independent of variations in acetyl-CoA/CoASH. The resting data are consistent with a central role for PDHa and citrate in the regulation of the glucose-fatty acid cycle in skeletal muscle, as classically proposed. However, in the present study Ace infusion was not effective in perturbing the glucose-fatty acid cycle during exercise.

In vitro requirements for formate dehydrogenase activity from Desulfovibrio

1986 ◽  
Vol 32 (5) ◽  
pp. 425-429 ◽  
Author(s):  
Mary Ann Riederer-Henderson ◽  
Harry D. Peck Jr.
Keyword(s):  
Methylene Blue ◽  
Cytochrome C ◽  
Dehydrogenase Activity ◽  
Electron Acceptor ◽  
Formate Dehydrogenase ◽  
Direct Reduction ◽  
Protein S ◽  
Benzyl Viologen

In Desulfovibrio the protein(s) involved in formate dehydrogenase activity have not been identified or characterized. In situ assays in polyacrylamide gels demonstrated that formate dehydrogenase from either D. gigas or D. vulgaris catalyzed the direct reduction of either methylene blue or benzyl viologen in the presence of formate. Thus, the same protein was active with either electron acceptor. Although the enzyme could be stored in air without irreversible inactivation by O2, activity with either dye was stimulated by the addition of thiols to the assay mixture. In the absence of formate the thiols served as a substrate for the in situ reduction of methylene blue or benzyl viologen by the enzyme. Ammonium sulfate fractionation revealed the presence of a fraction which selectively stimulated activity with either benzyl viologen or cytochrome c3 as the electron acceptor. The stimulating fraction was nondialyzable, heat labile, and unstable upon storage. The fraction from either species could stimulate the formate dehydrogenase activity of the other species. The protein may be of physiological signficance as it increased when the cells were grown on formate, and it stimulated the formate hydrogenlyase system with cytochrome c3 as the electron carrier.

Dichioroacetate Increases Skeletal Muscle Pyruvate Dehydrogenase Activity During Acute Limb lschemia

2003 ◽  
Vol 37 (3) ◽  
pp. 191-195 ◽  
Author(s):  
Jeffrey S. Wilson ◽  
Greg Rushing ◽  
Brad L. Johnson ◽  
Jeffrey A. Kline ◽  
Martin R. Back ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase
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