REGULATION OF PROSTAGLANDIN RECEPTORS IN MYOMETRIUM

前列腺素（PG）似乎有一个主要的作用，在启动 和/或维持分娩。 抑制前列腺素 合成被用作早产中安胎的机制，尽管 对胎儿有潜在的有害副作用 的 子宫肌层对PG的反应和敏感性可能由以下因素决定： 各种PG受体的差异表达，其中许多已被 最近克隆并测序的 PG受体是 G蛋白偶联受体超家族，具有七个跨膜 跨域。 每种前列腺素都有一个特定的受体 同种型与不同的信号转导途径相连， 收缩或舒张反应。 受体选择性剪接 mRNA转录物产生亚型，亚型可以与 不同的信号转导途径，作用不同。 所以 对任何特定前列腺素（例如PGE 2）的反应可能取决于 受体亚型及其亚型在任何特定时间表达。 子宫肌层中存在的受体亚型以前被认为是 以药理学手段为特征。 最近的克隆和测序 这些受体提供了批判性研究同种型的机会， 和亚型的存在，它们的个体发育在整个妊娠期和变化 分娩和荷尔蒙控制 不幸的是，具体 受体同种型的抗体和探针是不可用的。 一 该提案的主要目标是开发试剂， 促进这些研究。 待检验的总体假设是， 子宫对甘草素的反应性部分受 收缩型和舒张型PG受体的差异表达 在子宫肌层中存在同种型，并且这种表达受到子宫内膜的调节， 雌激素/孕激素 本研究的三个目标是：（1）识别和综合 每种受体同种型的独特肽序列， 用于免疫组织化学和蛋白质印迹研究（2）分离cDNA 用于大鼠和人子宫肌层的选定受体亚型 在原位杂交和北方分析和（3）研究 孕鼠子宫肌层受体亚型的调节 控制雌激素和孕激素的合成和作用。 描述PG受体的发生、个体发育和调节 在子宫肌层中是开始探索使用 刺激或抑制特定受体作为一种新的选择性 安胎的方法。 必要的第一步是发展 高质量的试剂，以帮助这项研究，并进一步用于探测 受体结构/功能关系。

Prostaglandins (PG s) appear to have a major role in the initiation and/or maintenance of parturition. Inhibition of prostaglandin synthesis is used as a mechanism of tocolysis in preterm labor, though not without potentially deleterious side effects for the fetus. The response and sensitivity of myometrium to PG's may be governed by differential expression of various PG receptors, many of which have been recently cloned and sequenced. The PG receptors are part of the superfamily of G protein-coupled receptors that have seven transmembrane spanning domains. Each prostaglandin species has a specific receptor isoform linked to a distinct signal transduction pathway giving contraction or relaxatory responses. Alternate splicing of receptor mRNA transcripts give rise to isoform subtypes that can be linked to different signal transduction pathways with diverse actions. Hence, the response to any particular prostaglandin (e.g. PGE2) may depend on the receptor isoforms and their subtypes expressed at any particular time. The receptor isoforms present in myometrium have previously been characterized by pharmacologic means. The recent cloning and sequencing of these receptors offers the opportunity to critically study isoforms and subtypes present, their ontogeny throughout gestation and changes with parturition and hormonal manipulation. Unfortunately, specific antibodies and probes to the receptor isoforms are not available. A principal objective of this proposal is to develop reagents to facilitate these studies. The overall hypothesis to be tested is that uterine responsivity to prostaglandins is in part regulated by differential expression of contractile and relaxatory PG receptor isoforms in myometrium and that this expression is hormonally regulated by estrogen/progesterone. The three objectives of the study are to (1) identify and synthesize unique peptide sequences for each receptor isoform to raise antibodies for immunohistochemistry and western blotting studies (2) isolate cDNA s for selected receptor isoforms from rat and human, myometrium for use in in situ hybridization and northern analysis and (3) study the regulation of receptor isoforms in pregnant rat myometrium by manipulation of estrogen and progesterone synthesis and action. Description of the occurrence, ontogeny and regulation of PG receptors in myometrium is a crucial first step in beginning to explore the use of stimulation of inhibition of specific receptors as a novel selective means of tocolysis. A necessary first step is the development of quality reagents to aid in this study and for further use in probing receptor structure/function relationships.