Premature onset of labor, neonatal patent ductus arteriosus, and prostaglandin synthetase antagonists--a rat model of a human problem.

Premature labor and patent ductus arteriosus are two potentially fatal hazards of the human newborn infant. Prostaglandin synthetase antagonists have thus been used to suppress early labor and to close the ductus of the neonate. Indomethacin has been most effective but not free of significant complications.

Studies on closure of the ductus arteriosus. X. In vivo effect of prostaglandin.

The effect of prostaglandins F2alpha, E1 and of 7-oxa-13-prostynoic acid on the newborn rabbit ductus can be studied using the whole-body freezing technique. PGF2alpha and PGE1 were able to re-open the closing ductus arteriosus in adequately oxygenated animals. PGF2alpha administration was accompanied by a strong physical reaction in the rat but less in the rabbit.

Studies on closure of the ductus arteriosus. XII. In utero effect of indomethacin and sodium salicylate in rats and rabbits.

Administration of prostaglandin synthetase inhibitors to pregnant does and dams in late gestation was followed by in utero contraction of the fetal ductus arteriosus when studied by the whole-body freezing method. In the rat this contraction was well established within 6 h and persisted up to 36 h following 15 mg/kg indomethacin p.o.