[Action of cortisol on electrocardiogram and heart metabolism in rats: influence of orchidectomy].

The action of cortisol on electrocardiogram and cardiac parameters such as cardiac weight in absolute value and relative to the corporal weight, in dry substance, and the nitrogen content of the organ, have been studied in normal (NC) and orchidectomized rats (C). Since cortisol causes an intake reduction, pair-feeding runs were conducted in order to achieve hormone action results unbiased by the effects derived from the intake restrictions. Cortisol has not change either the cardiac weight or its nitrogen content versus controls, although their parameters were found to diminish on account of the intake restriction linked to the treatment. Cortisol treatment determined also a cardiac weight increase relative to body weight by reducing the body weight of these animals. The cardiac frequency was increased by glucocorticoid action, but the increase was produced at the expense of shortening the PR intervals which pointed to a better auriculoventricular conduction. The R wave and the T wave voltages increased and decreased respectively from the cortisol action, being both clear signs of ventricular hypertrophy. Orchidectomy did not determine significant modifications either in cardiac function or metabolism.