Abstract
During the development of the "electrolytesteroid-cardiopathy with necroses" (ESCN) in rats, there is a decrease of myocardial potassium in the group bound to develop the cardiac necroses. A similar variation was observed in the control animals treated with a noncardiotoxic association of steroid and electrolytes. Only after the necrosis had been established was an important increase of sodium and decrease of potassium observed. On the basis of these and other previously deseribed facts, the author concludes that, although it is conceivable that the diminution of potassium in the heart could favor the development of the necroses, the hypothesis of the ESCN as a result of a simple potassium depletion cannot be accepted.