Michael F. Allard

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The contribution of glycolysis and oxidative metabolism to ATP production was determined in isolated working hypertrophied hearts perfused with Krebs-Henseleit buffer containing 3% albumin, 0.4 mM palmitate, 0.5 mM lactate, and 11 mM glucose. Glycolysis and glucose oxidation were directly measured by perfusing hearts with [5-3H/U-14C]glucose and by(More)
Glucocorticoids impair insulin sensitivity. Because insulin resistance is closely linked to increased incidence of cardiovascular diseases and given that metabolic abnormalities have been linked to initiation of heart failure, we examined the acute effects of dexamethasone (DEX) on rat cardiac metabolism. Although injection of DEX for 4 h was not associated(More)
OBJECTIVE The purpose of the present study was to determine whether increased activation of the RhoA/Rho-kinase (ROCK) pathway occurs in diabetic cardiomyopathy and whether acute inhibition of this pathway improves contractile function of the diabetic heart. METHODS Male Wistar rats were made diabetic with streptozotocin. Twelve to fourteen weeks later,(More)
OBJECTIVES Transcatheter aortic valve replacement (AVR) is a promising approach to aortic valve disease. The implications of this new therapy are not entirely known. We describe the potential for the development of new atrioventricular (AV) block. BACKGROUND Atrioventricular block is a known complication of conventional surgical AVR. Block is presumed to(More)
OBJECTIVES We sought to determine whether improving coupling between glucose oxidation and glycolysis by stimulating glucose oxidation during reperfusion enhances postischemic recovery of hypertrophied hearts. BACKGROUND Low rates of glucose oxidation and high glycolytic rates are associated with greater postischemic dysfunction of hypertrophied as(More)
Adaptation of myocardial energy substrate utilization may contribute to the cardioprotective effects of regular exercise, a possibility supported by evidence showing that pharmacological metabolic modulation is beneficial to ischemic hearts during reperfusion. Thus we tested the hypothesis that the beneficial effect of regular physical exercise on recovery(More)
BACKGROUND Rates of glycolysis from exogenous glucose are accelerated in hypertrophied hearts. In this study, we determined whether alterations in the metabolism of glycogen, an endogenous storage form of glucose, also occur in hypertrophied hearts. METHODS AND RESULTS Rates of glycolysis ([3H]H2O production) and oxidation ([14C]CO2 production) from(More)
We tested the hypothesis that myocardial substrate supply regulates fatty acid oxidation independent of changes in acetyl-CoA carboxylase (ACC) and 5'-AMP-activated protein kinase (AMPK) activities. Fatty acid oxidation was measured in isolated working rat hearts exposed to different concentrations of exogenous long-chain (0.4 or 1.2 mM palmitate) or(More)
Accelerated glycolysis in hypertrophied hearts may be a compensatory response to reduced energy production from long-chain fatty acid oxidation with 5'-AMP-activated protein kinase (AMPK) functioning as a cellular signal. Therefore, we tested the hypothesis that enhanced fatty acid oxidation improves energy status and normalizes AMPK activity and glycolysis(More)
Propionyl L-carnitine (PLC) is a naturally occurring derivative of L-carnitine that can improve hemodynamic function of hypertrophied rat hearts. The mechanism(s) responsible for the beneficial effects of PLC is not known, although improvement of myocardial energy metabolism has been suggested. In this study, we determined the effect of PLC on carbohydrate(More)