The response of isolated rat heart cells to cardiotoxic concentrations of isoprenaline.

Isolated beating rat heart myocytes were incubated with the the sympathomimetic amine isoprenaline at concentrations which are known to induce myocardial necrosis in vivo. Incubation with isoprenaline did not induce changes in cell morphology nor impair the ability of the cells to take up and retain fluorescein diacetate. These results suggest that myocardial cells are not the main target in isoprenaline-induced necrosis and that some alternate indirect mechanism must be involved.