Influence of oxytocin on prostaglandin E-2, intracellular calcium, and cyclic adenosine monophosphate in human amnion-derived (WISH) cells

OBJECTIVE: This study was undertaken to investigate the regulation of prost aglandin release by oxytocin and the influence of oxytocin on intracellular calcium and on the cyclic adenosine monophosphate system in human amnion-d erived WISH cells. STUDY DESIGN: We determined prostaglandin E-2 release from WISH cells treat ed with oxytocin, evaluated the cytosolic calcium concentration in single W ISH cells by confocal microscopy, and measured both intracellular cyclic ad enosine monophosphate levels and adenylyl cyclase activity after oxytocin t reatment. RESULTS: Treatment of WISH cells with oxytocin resulted in a concentration- dependent release of prostaglandin E-2, which was increased by lithium chlo ride and inhibited by indomethacin and U-73122. In single WISH cells, oxyto cin increased cytosolic calcium. Moreover, the hormone lowered levels of in tracellular cyclic adenosine monophosphate but did not alter adenylyl cycla se activity. CONCLUSIONS: Our data demonstrate, for the first time, that WISH cells resp ond to oxytocin by increasing prostaglandin E-2 release. In addition to pho spholipase C activation and cytosolic calcium increase, the hormone effect involves also a reduction of the cyclic adenosine monophosphate level.