Avian oviduct motility induced by prostaglandin E1.

Oviduct segments from infundibulum, magnum, uterus, utero-vaginal junction and vagina of actively laying hens at preoviposition time were tested for their contractile reaction to prostaglandin E1 by in vitro or in vivo methods. Maximum stimulatory response was observed from the muscular strips of the proximal oviduct segment (infundibulum) and a complete relaxation was recorded from the distal part (vagina) at molar concentrations of 1.4 X 10(-7), 3.4 X 10(-7) and 7.0 X 10(-7). The uterine strips reacted with a stimulatory response at higher concentrations (1.4 X 10(-6) and 2.8 X 10(-6) moles), but lacked any significant change at lower concentrations. The uterovaginal muscular strips showed a mild but prolonged inhibitory response, while the magnum responded with a significant increase in the luminal pressure when tested in vivo. It is concluded that PGE1 exerts a stimulatory effect on the uterus to initiate transport of the egg to subsequent segments (utero-vaginal junction and vagina), which relax under PGE1 influence and allow passage of the egg by pressure differences.