पृष्ठ 1 से 19 परिणाम
Hexokinase (HK) II content is elevated in fatigue resistant muscle fibres and exercise trained muscle. The aim of this study was to determine if exercise capacity is dependent on muscle HK protein content. C57Bl/6 mice with a 50% HK knockout (HK+/-), no genetic manipulation (wild-type, WT) and an
We previously demonstrated that hexokinase (HK) II plays a key role in the pathophysiology of ischemia-reperfusion (I/R) injury of the heart (Smeele et al. Circ Res 108: 1165-1169, 2011; Wu et al. Circ Res 108: 60-69, 2011). However, it is unknown whether HKII also plays a key role in I/R injury and
This study investigates early adaptive responses of fast-twitch muscle to increased contractile activity by low-frequency stimulation. Changes in metabolite levels and activities of regulatory enzymes of carbohydrate metabolism were investigated in rabbit tibialis anterior muscle after 24 h of
The effect of bicycle exercise (75% of maximal oxygen uptake) on glucose uptake by the inferior limb (LGU) and glycolysis in human skeletal muscle has been investigated. Biopsies were obtained from the quadriceps femoris muscle before exercise, after 5 and 40 min of exercise, and at fatigue [74.9
Malnourished surgical patients have metabolic and functional abnormalities of skeletal muscle and it has been suggested that these are due to reduced activities of glycolytic enzymes associated with abnormalities of muscle fibres. We have measured the activities of four key enzymes of glucose
BACKGROUND
Alterations in skeletal muscle function are known to contribute to exercise intolerance in patients with chronic heart failure (CHF).
OBJECTIVE
To evaluate whether muscle isometric endurance can be objectively measured and whether it is related to skeletal muscle metabolism in
This study describes the influence of muscle fiber type composition, enzyme activities and capillary supply on muscle strength, local muscle endurance or aerobic power and capacity. Muscle biopsies were obtained from m. vastus lateralis in thirteen physically active men. Histochemical staining
Alterations in enzyme activities involved in muscle energy metabolism and the muscle fiber type distribution were investigated in six subjects, ranging in age from 19-23 years, following short-term, high intensity exercise. Changes in the vastus lateralis muscle were studied prior to exercise and
BACKGROUND
Exertional fatigue, which frequently limits exercise in patients with chronic heart failure, is associated with early anaerobic metabolism in skeletal muscle. The present study was designed to examine the skeletal muscle metabolic response to exercise in this disorder and determine the
Isometric contraction of the quadriceps muscle sustained to fatigue with a force of 66% of the maximum voluntary contraction force resulted in a mean glycogen utilization of 80.4 (S.D. 58.4) mmol glucosyl units/kg dry muscle (d.m.) and an accumulation of glycolytic intermediates and glucose
In the process of defining the recruitment of fuel and pathway selection in rainbow trout fast-twitch white skeletal muscle, it was clear that the near-maximal myosin adenosinetriphosphatase activity during a 10-s sprint was supported solely by phosphocreatine hydrolysis. A conservative estimate of
The content of glucose 1,6-bisphosphate (G-1,6-P2), an in vitro activator of phosphofructokinase (a rate-limiting enzyme for glycolysis), and the glycolytic rate in skeletal muscle during isometric contraction have been determined. Subjects contracted the knee extensor muscles at two-thirds maximal
Leg glucose uptake (LGU) during submaximal (50% maximal O2 uptake) and maximal dynamic exercise (97%) has been quantified from the product of the leg blood flow and the arterial minus femoral venous glucose concentration. Muscle biopsies were also obtained. During 15 min of submaximal exercise the
The effect of fatigue (running to exhaustion) on the Vmax activity of the key glycolytic enzymes measured at saturating substrate concentrations in muscles, liver and brain of sedentary and trained (running on a treadmill one h/day at 20 m/min, five days/week for six months) female Zucker fatty rats
The skeletal muscle has the capacity to respond adaptively to increased use. This observation could open up the feasibility of constructing pumping chambers to support or even replace cardiac work. We investigated the changes in enzyme activity due to chronic stimulation in an animal skeletal