Abstract: | The distribution of prostaglandin E2 and F2 alpha was examined in the peripheral veins and in several positions of the cardiovascular system before and after the blood had passed through the lungs in 37 infants. Prostaglandin E2 varied from 0.25 +/- 0.09 ng/ml to 0.44 +/- 0.09 ng/ml when measured in the pulmonary artery, the ductus arteriosus, the right atrium, the right ventricle, the left atrium, the left ventricle, the inferior vena cava and the descending aorta. Prostaglandin F2 alpha was much higher in these positions of the cardiovascular system. The range was 0.99 +/- 0.36 ng/ml to greater than 2.0 ng/ml. The vascular tissues produced virtually identical high amounts of prostaglandin E2 and F2 alpha, but there were no significant differences in prostaglandin E2 and F2 alpha, concentrations, in venous blood as well as in systemic arterial blood. The results suggest that prostaglandin E2 is not responsible for the persisting patency of the ductus arteriosus in infants. There is no explanation for the increased prostaglandin F2 alpha concentrations in these patients. |