Effect of gestational age on ductus arteriosus response to circulating prostaglandin E2*

https://doi.org/10.1016/S0022-3476(83)80023-7Get rights and content

Premature newborn lambs with a patent ductus arteriosus have higher plasma prostaglandin E2concentrations than near-term newborn lambs with a contricted ductus arteriosus. To see whether these concentrations of PGE2 could produce patency of the ductus arteriosus, we studied eight near-term lambs (with constricted ductuses) delivered by cesarean section, paralyzed, and mechanically ventilated. After ductus arteriosus resistance and plasma PGE2 concentrations had stabilized, a continuous PGE2 infusion into the superior vena cava was started to determine threshold concentrations needed to dilate the ductus in vivo. By two hours after birth, circulating PGE2 concentrations in near-term lambs were considerably less then the threshold concentration, and the ductures were constricted. In five premature newborn lambs, significantly lower concentrations of PGE2 were required to dilate the ductus: threshold and ED50 concentrations were one sixth and one third, respectively. In these premature lambs during the first two hours after birth, circulating PGE2 concentrations were twice as high as the calculated in vivo threshold level. Therefore, circulating PGE2 concentrations probably played a significant role in the patency of the ductus arteriosus in these premature lambs.

References (18)

There are more references available in the full text version of this article.

Cited by (0)

*

Supported by grants from the United States Public Health Service, Program Project HL24056 and SCOR HL27356.

View full text