[Effect of OU-1308 on uterine motility in pregnant rats and monkeys].

Effect of OU-1308 (17s, 20-dimethyl-6-oxo-prostaglandin E1 methyl ester) on uterine motility in anesthetized rats and monkeys was examined by means of the balloon catheter or open-end catheter method and compared with that of PGF2 alpha. OU-1308 and PGE2 alpha exhibited uterine contractile activity at the dose of 30 micrograms/kg, i.v., on day 8 of pregnancy and 10 micrograms/kg, i.v., on day 20 of pregnancy in rats. In monkeys on day 50 approximately 120 of pregnancy, both compounds enhanced uterine motility at 10 micrograms/kg, i.v. Intragastric administration of OU-1308 at 500 micrograms/kg, however, was without effect in monkeys. These results indicate that when administered intravenously, OU-1308 was as potent as PGF2 alpha in terms of uterine contractile activity in pregnant rats and monkeys.