Influence of insulin on protein metabolism and cardiac glycogen in Houssay animals

The urinary nitrogen excretion of hypophysectomized-depancreatized (Houssay) cats on constant diets was measured before and during the administration of insulin. Metabolic periods of 4–8 days were used. Nitrogen retention occurred in the absence of the anterior pituitary, when urinary glucose was reduced by 5 gm or more during insulin treatment. Otherwise, retention of nitrogen did not occur. Conventional calculation of the total utilization of glucose for these and control groups of animals suggest that the amount of change in glucose utilization and secondary hormonal effects exert more influence on protein metabolism than the actual amount of carbohydrate used. Restoration of hepatic tissue (protein) was grossly demonstrable. In animals lacking insulin, the anterior pituitary, or both, cardiac glycogen appeared to be significantly related to the level of blood glucose.

Spectroscopic effects of adenosine diphosphate upon the respiratory pigments of rat-heart-muscle sarcosomes

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Hemodynamic determinants of oxygen consumption of the heart with special reference to the tension-time index

The hemodynamic determinants of myocardial oxygen utilization were ascertained in the isolated, metabolically supported, nonfailing canine heart. The primary determinant was found to be the total tension developed by the myocardium as indicated by the area beneath the systolic pressure curve (Tension-Time Index). The significance of these findings for the understanding of the low efficiency of the failing heart and the consequently increased importance of Laplace's law are discussed.