Uterine contractility in response to different prostaglandins: results from extracorporeally perfused non-pregnant swine uteri

BACKGROUND: Prostaglandins (PGs) are important stimulators of uterine contractility. Limited data are available at present on the effects of different PGs on uterine contractility, measured using intraluminal pressure changes in the complete uterus. The goal of this study was to assess dynamic changes in uterine contractility and peristalsis in response to PGs in comparison with the effects of oxytocin administration. METHODS: An extracorporeal perfusion model of swine uteri was used, which keeps the uterus in a functional condition, and is appropriate for the study of physiological questions. Oxytocin- and PG-induced uterine contractility and peristalsis were assessed using an intrauterine double-chip microcatheter. RESULTS: A dose-dependent increase in intrauterine pressure (IUP) in the isthmus uteri (P < 0.001) and the corpus uteri (P < 0.001) was observed after the administration of PGF(2 alpha) and oxytocin, which reached a plateau after further stimulation. A dose-dependent increase in IUP in the isthmus uteri (P < 0.001) and the corpus uteri (P < 0.001) was also observed after the administration of PGE(1) and PGE(2), with a plateau in IUP in the middle-concentration range and a decrease in the course of further stimulation. PGE(2) caused significantly more contractions starting in the corpus uteri and moving to the isthmus uteri (P = 0.008). The direction of most contractions caused by PGE(1), PGE(2) and oxytocin differed from that of PGF(2 alpha). CONCLUSIONS: This study demonstrates that the PGs tested modulate contractility in non-pregnant swine uteri in a characteristic way, resulting in different contractility patterns.