Myocardial Carbohydrate Metabolism
نویسندگان
چکیده
Myocardial metabolism of Nembutalized normal intact dogs was studied with the aid of the coronary sinus catheterization technic. Oxygen, glucose, lactate and pyruvate were extracted by the heart in direct relation to the arterial level of each substance, independently of the others. Pyruvate and lactate showed a high myocardial extraction coefficient, but the normal low arterial levels at rest prevented them from together accounting for more than 50 per cent of the total myocardial energy requirements. Glucose was not utilized below a mean threshold of 54 mg. per cent, but with normal arterial levels of 70 to 1 20 ing. per cent, glucose extraction was sufficient to provide the major potential source of fuel for myocardial oxidative energy. During starvation, the heart probably derived its energy from fat, as indicated by a myocardial respiratory quotient near 0.70, and a low myocardial carbohydrate extraction.
منابع مشابه
Coronary blood flow, myocardial oxygen consumption, and myocardial metabolism in normal and hyperthyroid human subjects.
The effects of thyroid hormone excess on myocardial hemodynamics and carbohydrate metabolism were determined in a group of subjects, and the findings compared with those obtained in a group of normal individuals. The results indicate that in thyrotoxicosis there tends to be an increase in coronary blood flow and myocardial oxygen consumption and a normal per cent extraction of oxygen by the myo...
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