Effect of pulmonary circulation on coronary flow and ventricular performance of isolated heart

Left ventricular performance and coronary flow in isolated dog hearts were observed for to discuss whether lungs have any nonrespiratory function. The results of our experiments showed the fact that pulmonary circulation seemed to have some metabolic functions to prevent the increase in coronary flow and the decline in ventricular performance. And it was also suggested that isolated lungs removed a factor responsible for coronary vasodilation and the decline of ventricular performance. But it could not be fully negrected that the pulmonary circulation added a factor which prevents the increase in coronary flow.