glycogen and Intermittent-Claudication

Topics: Biopsy; Exercise Therapy; Glucose; Glycogen; Humans; Intermittent Claudication; Leg; Lipid Metabolism; Mitochondria, Muscle; Muscles; Physical Exertion; Placebos; Regional Blood Flow; Succinate Dehydrogenase; Time Factors

1. We set out to define abnormalities of oxidative ATP synthesis, cellular proton efflux and the efficiency of ATP usage in gastrocnemius muscle of patients with claudication due to peripheral vascular disease, using data obtained by 31P magnetic resonance spectroscopy during aerobic exercise and recovery. 2. Eleven patients with moderate claudication were studied and results were compared with 25 age-matched control subjects. Changes in pH and phosphocreatine concentration during recovery were used to calculate the maximum rate of oxidative ATP synthesis (Qmax.) and the capacity of net proton efflux. Changes in pH and phosphocreatine concentration were used to estimate rates of non-oxidative and (indirectly) oxidative ATP synthesis throughout exercise, taking account of abnormalities in proton efflux during exercise. 3. In patients with claudication, slow post-exercise phosphocreatine recovery showed a 42 +/- 9% decrease in Qmax., and the slow ADP recovery was consistent with this. pH recovery was slow, showing a 77 +/- 9% decrease in the capacity for proton efflux. Both abnormalities are compatible with a substantial reduction in muscle blood flow. 4. During exercise, increased phosphocreatine depletion and intracellular acidification were a consequence of impaired oxidative ATP synthesis and the consequent increase in non-oxidative ATP synthesis, compounded by reduced proton efflux. The acidification prevented an increase in ADP concentration which could otherwise partially compensate for the oxidative defect. All these abnormalities are compatible with a reduced muscle blood flow. 5. In addition, initial-exercise changes in pH and phosphocreatine concentration implied a 44 +/- 5% reduction in 'effective muscle mass', necessitating an ATP turnover (per litre of muscle water) twice as high for given power output as in control muscle. Some of this is probably due to a localized loss of muscle fibres, but the rest appears to reflect reduced metabolic efficiency of the muscle. This is not a direct consequence of reduced blood flow, and may be related to change in muscle fibre type.

Topics: Adenosine Triphosphate; Adult; Aged; Aged, 80 and over; Case-Control Studies; Female; Glycogen; Humans; Intermittent Claudication; Magnetic Resonance Spectroscopy; Male; Middle Aged; Mitochondria, Muscle; Muscle, Skeletal; Peripheral Vascular Diseases; Phosphorus Radioisotopes

In addition to the determination of the presenting symptom of patients with peripheral vascular occlusive disease, evaluation of these patients may include the noninvasive measurements of ankle/arm pressure ratio, limb blood flow, and treadmill testing to evaluate the severity of the reduction in blood flow. We have included metabolic studies to assess the effect of this reduced blood flow in patients with stable intermittent claudication (n = 20), and with end-stage ischemia (night and rest pain) (n = 11), and in a control group without vascular disease (n = 8). No correlations were found between the resting limb blood flow, ankle/arm pressure ratios, maximum walking distance, and stated walking distance for the patients with stable claudication. Although the oxygen consumption was reduced only in the patients with end-stage ischemia, the percent oxygen extraction was increased to the same level in the patients with stable claudication and those with end-stage ischemia. Intramuscular stores of high-energy phosphates and glycogen were maintained in all groups with the lactate/pyruvate ratio increased only in the patients with end-stage ischemia. The complex interrelationships between the rate and distribution of blood flow with exercise and enzyme adaptation in patients with vascular disease make current resting hemodynamic and metabolic evaluations a poor reflection of the severity of the clinical condition within each patient group. Therefore laboratory testing may offer no advantage over clinical presentation in the overall evaluation of these patients.

Topics: Adenosine Triphosphate; Adult; Aged; Blood Pressure; Glycogen; Humans; Intermittent Claudication; Ischemia; Lactates; Lactic Acid; Leg; Middle Aged; Muscles; Oxygen Consumption; Phosphocreatine; Pyruvates; Pyruvic Acid; Regional Blood Flow

Topics: Arterial Occlusive Diseases; Energy Metabolism; Glucose; Glycogen; Humans; Intermittent Claudication; Male; Physical Exertion

Twenty-four biopsy specimens from the lower leg muscles of 21 patients with intermittent claudication were studied by electron microscopy. Sixteen of the specimens contained hypertrophic, atrophic, autolytic, or phagocytic fibers, or other forms of macroscopic fiber degeneration. Of the pathological changes in the cell organelles, the most common was simple myofibrillar degeneration, followed by slightly pathological mitochondria and excessive accumulations of glycogen and lipofuscin. Different types of basement membrane alterations and central nuclei were present in 16 of the biopsy specimens. Most of the pathological changes were the same as those previously reported by others to occur in specific diseases of muscle. There was some positive correlation of the degree of pathological changes to the estimated clinical severity of claudication.

Topics: Aged; Basement Membrane; Biopsy; Female; Glycogen; Histocytochemistry; Humans; Intermittent Claudication; Male; Middle Aged; Muscles; Myofibrils; Phagocytosis; Vacuoles

The metabolic capacity of leg muscles was determined in 12 patients with peripheral arterial insufficiency before and 6 months after vascular surgery. Succinic oxidase activity and the incorporation rates of glucose-carbon into glycogen, lipids, lacate, and CO2 were determined as a measure of metabolic capacity. Leg muscles from patients with intermittent claudication had high metabolic capacity, as shown previously. This capacity was reduced towards control values after successful revascularizations, while it remained unchanged if the surgery failed. In patients with gangrene the preoperative values of leg muscles' metabolic capacity were subnormal, and increased towards control values if surgery was successful. In 2 patients with limb gangrene the vascular surgery was only partially successful i.e. the gangrene threat was changed into intermittent claudication. In these 2 patients the metabolic capacity of leg muscles changed from sub- to supracontrol values. In 2 patients the vascular surgery failed, and the patients had no benefit from the operation. In these 2 patients the metabolic capacity of leg muscles remained unchanged. These results support the theory that changes in the amount of blood flow, i.e. the supply of oxygen and substrates to the leg, govern the level of metabolic capacity of the skeletal muscles. The results seem to justify the recommendation that reconstructive arterial surgery in patients with intermittent claudication ought to be followed by physical training to preserve the high metabolic capacity in the skeletal muscles.

Topics: Aged; Arterial Occlusive Diseases; Biopsy; Blood Flow Velocity; Carbon Dioxide; Cholesterol; Female; Femoral Artery; Follow-Up Studies; Gangrene; Glycogen; Humans; Iliac Artery; Intermittent Claudication; Lactates; Lipid Metabolism; Male; Middle Aged; Muscles; Phospholipids; Succinate Dehydrogenase; Triglycerides

The relationship between the glycogen content of the vastus lateralis muscle and the working duration was determined in 6 patients with intermittent claudication. The working duration was determined on a bicycle ergometer at a load of 450 kpm/min. Muscle glycogen was determined in percutaneous needle biopsy specimens. The resting glycogen content in the vastus muscle increased significantly after depletion of the stores by physical exercise followed by glucose feeding for 2 days. This increase was associated with an increased working duration. This improvement of the working duration connected with high muscle glycogen content was a temporary phenomenon. When the duration was measured shortly after exercise, i.e. after depletion of the glycogen stores it was reduced to the preexperimental level. The improved working duration associated with increased glycogen content of leg muscles did not seem to be related to the improved walking capacity in claudication patients after physical conditioning.

Topics: Aged; Female; Glucose; Glycogen; Humans; Intermittent Claudication; Leg; Male; Middle Aged; Muscles; Physical Exertion; Stimulation, Chemical

Topics: Blood Glucose; Carbohydrate Metabolism; Carbon; Carbon Dioxide; Female; Glucose Tolerance Test; Glycogen; Humans; In Vitro Techniques; Insulin; Intermittent Claudication; Lipids; Male; Middle Aged; Muscles; Physical Education and Training; Succinate Dehydrogenase; Triglycerides

Topics: Adenosine Triphosphate; Adult; Exercise Test; Glycogen; Humans; Intermittent Claudication; Lactates; Leg; Male; Middle Aged; Muscles; Oxygen Consumption; Phosphocreatine; Physical Exertion; Regional Blood Flow

Topics: Aged; Arterial Occlusive Diseases; Carbon; Carbon Dioxide; Female; Glucose; Glycogen; Humans; Intermittent Claudication; Ischemia; Lactates; Leg; Lipids; Male; Middle Aged; Muscles; Succinate Dehydrogenase

Topics: Glycogen; Humans; Intermittent Claudication; Kinetics; Lipidoses; Muscles

Topics: Adolescent; Carbohydrate Metabolism, Inborn Errors; Diagnosis, Differential; Glycogen; Humans; Intermittent Claudication; Male; Muscular Diseases