The developmental effects of prostaglandin D2 on the pulmonary and systemic circulations in the newborn lamb.

Prostaglandin D2 (PGD2) lowers pulmonary arterial blood pressure without changing systemic arterial blood pressure in fetal and newborn lambs but increases pulmonary arterial pressure in older animals. We investigated the effect of PGD2 on the circulation in 15 newborn lambs, some studied intermittently from 1 to 30 days of age, with induced pulmonary arterial hypertension. PGD2 was infused intravenously in doses of 1 to 25 micrograms/kg per min.