Enzyme activity in the myocardium in experimental hypertension.

Abstract

The activities of myocardial enzyme were determined in heart muscle of normal and hypertensive rats to investigate the changes in cardiac metabolism in the experimentally induced renal hypertension.In the myocardium under the effect of long-standing hypertension caused by Masugi-nephritis, the activities of G-6-PDH, GAPDH and LDH demonstrated a statistically significant increase, whereas the activities of GK and PFK showed a statistically significant reduction.In the heart muscle of rats with hypertension induced by Goldblatt's experiment, the activities of G-6-PDH and αGPDH indicated a statistically significant increase, while the activities of PFK, ICDH and MDH demonstrated a statistically significant decrease. The activity of GAPDH showed a tendency to increase.The changes in myocardial enzyme patterns in the experimentally induced renal hypertension indicate an impairment of oxidative breakdown and increase in anaerobic glycolysis through the pentose monophosphate shunt. These results were well in agreement with the data of previous study on the effect of acute systemic overloading upon the heart and experimentally induced heart failure.From these deducements, it can be conceived that there is a metabolic defect in the myocardium in experimental hypertension.