[On the effect of PGE2 and PGF2 alpha on circular and longitudinal myometrium strips of different corpus uteri tissues of the guinea pig in vitro (author's transl)].

The effects of PGE2 and PGF2 alpha on corpus uteri and cervix strips of guinea pigs were studied in vitro. Myometrium strips developed maximal contraction activity at concentrations of 10(-7) M PGE2 and 5 x 10(-7) M PGF2 alpha in the organ bath, respectively. As for corpus uteri myometrium strips, longitudinal (extern) and circular (intern) layers of the organ wall showed comparable Prostaglandin-induced contractions. On the other hand, longitudinal and circular strips from cervix uteri tissue showed adverse Prostaglandin effects: PGE2 relaxed the cervix strips by lowering the muscle tone, the contraction frequency and a complete stop of contractions within most experiments lasting for an average time of 15 min. PGF2 alpha induced strong contractions of the same kind like corpus uteri strips did. The results indicate a role of PGE2 in the opening of the cervix, whereas PGF2 alpha possibly plays a role in the involution of the uterus post partum.