[Effect of prostaglandin E1 on the isolated stomach, small intestine, bronchus and uterus of experimental animals and its intestinal effect in vivo].

The stomach, intestine and uterus were contracted by PGE1. Stimulating effects of ACh and serotonin were augmented in some of these organs, especially in guinea pig uterus. ACh- and serotonin-induced bronchial contraction, however, decreased after administration of PGE1. Bronchial relaxation induced by adrenaline or noradrenaline was unaffected or increased. Antiadrenergic effects were not detected in the organs tested. ACh-induced contractions of frog rectus abdominus was augmented by PGE. The potentiating effect of PGE1 was almost the same in degree as that of physotigmine, although cholinesterase inhibitory effect was not detected in PGE1. Intravenous injection of PGE1 (10 mug/kg) into rabbits caused a relaxation of the intestine, which was contrary to the result with the isolated organ. Administration of PGE1 (1 mug/100 g, i.p. or 0.1, 1 mug/100 g, i.v.) did not show any curative effects on intestinal paralysis in cecectomized rats. The mechasism of action of PGE1 on rat uterus was found to be calcium-dependant.