Regulation of Prostaglandin E Synthases in Parturition

描述（由申请人提供）：子宫内前列腺素（PGs）在足月和早产儿分娩过程中起近端介质的作用。妊娠组织中子宫强直pg（尤其是PGE2）的产生主要通过诱导酶环氧化酶-2 （COX-2）的转录上调途径发生。直到最近，人们还认为COX-2反应产物PGH2产生终末前列腺素的过程迅速且不受特殊控制。这一观点随着最近两种具有PGH到POE异构酶活性的酶的表征而改变，人们发现这些酶，微粒体前列腺素E合成酶（PGES）和细胞质PGES，在炎症条件下对PGE2的产生贡献不平等。在这项提议中，我们打算表征这两种PGES亚型与COX-2的表达模式。这将在模拟炎症条件下使用人羊膜来源的WISH细胞和人羊膜原代培养物来完成。我们建议结合免疫细胞化学，在信使RNA水平和蛋白水平（在全细胞裂解物和亚细胞组分中）表征微粒体和细胞质PGES的表达模式。我们希望支持这样的假设，即在其他系统中，微粒体PGES在子宫张力POE2的产生中与COX-2有功能联系。

DESCRIPTION (provided by applicant): Intrauterine prostaglandins (PGs) act proximal mediators in the process of parturition, both at term and preterm. The production of uterotonic PGs (particularly PGE2) within gestational tissues occurs primarily via a pathway involving transcriptional up-regulation of the inducible enzyme, cyclooxygenase-2 (COX-2). Until recently, the generation of terminal prostanoids from the COX-2 reaction product, PGH2, was thought to occur rapidly and under no particular control. This view has changed with the recent characterization of two enzymes possessing PGH to POE isomerase activity, It has been discovered that these enzymes, microsomal prostaglandin E synthase (PGES) and cytosolic PGES, contribute unequally to the generation of PGE2 under inflammatory conditions. In this proposal, we intend to characterize the expression patterns of these two PGES isoforms in relation to COX-2. This will be done using human amnion-derived WISH cells and primary cultures of human amnion, under simulated inflammatory conditions. We propose to characterize the expression patterns of microsomal and cytosolic PGES at the messenger RNA level and at the and at the protein level (in both whole cell lysates and subcellular fractions), combined with immunocytochemistry. We hope to support the hypothesis that, as in other systems, microsomal PGES is functionally linked to COX-2 in the generation of uterotonic POE2.