前列腺素(PG)是强力的血管活性物质,存在于已测定过的人类所有组织中。在成人,肺部能起中和作用的酶,可将进入静脉系统的PG约95％消除。但在胎儿循环,PG能通过动脉导管(及其他分流)绕过肺血管床,并作为循环的血管活性激素对大的动脉(包括动脉导管)起作用。体外实验表明,PGE类有使羊、牛及人的动脉导管扩张的作用。PGF2α能使牛及人的动脉导管收缩,使兔的扩张。Coceani等 Prostaglandin (PG) is a potent vasoactive substance found in all human tissues that have been measured. In adults, enzymes that neutralize the lungs can eliminate about 95% of the PG entering the venous system. However, during fetal circulation, PG can bypass the pulmonary vascular bed through the ductus arteriosus (and other shunts) and act as a circulating vasoactive hormone on large arteries, including the ductus arteriosus. In vitro experiments show that PGE class sheep, cattle and human ductus arteriosus expansion. PGF2α can make bovine and human ductus contractions, the expansion of the rabbit. Coceani et al