Regulation of Prostaglandin E Synthases in Parturition

描述(申请人提供)：宫内前列腺素(PGs)在足月和早产的分娩过程中扮演近端介体的角色。在妊娠组织中，子宫强直性前列腺素(尤其是PGE2)的产生主要通过一条途径发生，该途径涉及到诱导酶环氧合酶-2(COX-2)的转录上调。直到最近，从COX-2反应产物PGH2中产生末端前列腺素被认为是快速发生的，并且没有特殊的控制。随着最近对两种具有PGH到POE异构酶活性的酶的鉴定，这种观点已经改变，人们发现这两种酶，微粒体前列腺素E合成酶(PGES)和胞质前列腺素E合成酶，在炎症条件下对PGE2的产生起着不同的作用。在这项建议中，我们打算表征这两种pGES亚型与COX-2的表达模式。这将使用人羊膜来源的Wish细胞和人羊膜的原代培养，在模拟炎症条件下完成。我们建议结合免疫细胞化学，在信使RNA水平和蛋白水平(在整个细胞裂解产物和亚细胞组分中)表征微粒体和胞质PGES的表达模式。我们希望支持这一假设，就像在其他系统中一样，在子宫强直性POE2的产生中，微体PGES在功能上与COX-2有关。

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.