PAF STIMULATED PHOSPHOINOSITIDE TURNOVER IN PLATELETS

血小板活化因子(PAF)是一种磷脂，具有特定的结构 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine(AGEPC)。它会影响 几种细胞和组织的功能。最显著的影响是 这种化合物存在于血小板上，这是一种血细胞，在 心血管过程。AGEPC刺激血小板，也导致快速 聚磷脂酰肌醇周转率(PPI)主题是为了阐明 AGEPC的“机制”和“重要性”刺激了PPI周转 血小板。根据新的实验发现，我们的假设是 磷酸肌醇磷酸二酯酶(磷脂酶C)在 AGEPC刺激血小板活化。 以下实验策略将构成该项目的基础 [I]确定关键酶(磷脂酶C)的特性 参与PPI周转；由选定的代理进行调节。 [II]PPI周转率与AGEPC受体的关系 受体a PPI磷酸二酯酶？ [III]PPI周转与血小板之间可能联系的研究 对AGEPC不敏感(脱敏)。 [IV]AGEPC促进血小板PPI转换率的原位研究 被操纵的PPI水平；或来自病理生理状态的血小板。 AGEPC正在成为一种强有力的调解人(蝶形突触)。PPI成交额正在下降 支持作为小区信令事件。这种信号机制是怎样的？ 参与这种新的介质(AGEPC)的生化作用模式是 因此，这是一个重要的问题。这将使用血小板作为一种 模型单元。

Platelet activating factor (PAF), a phospholipid, has an assigned structure of 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC). It affects the function of several cells and tissues. The most pronounced effect of this compound is on platelets, a blood cell with important role in cardiovascular processes. AGEPC stimulates platelets and also causes rapid turnover of polyphosphoinositides (PPI). The theme is to elucidate the 'mechanism" and "importance' of AGEPC stimulated PPI turnover in platelets. Based on new experimental findings it is our hypothesis that phosphoinositide phosphodiesterase (phospholipase C) plays a key role in AGEPC stimulated activation of platelets. The following experimental strategies will form the basis of this project [I] To establish characteristics of the key enzyme (phospholipase C) involved in PPI turnover; its regulation by selected agents. [II] Relationship between PPI turnover and AGEPC receptor; Is AGEPC receptor a PPI phosphodiesterase? [III] Study of possible link between PPI turnover and platelet refractoriness (desensitization) to AGEPC. [IV] Study of AGEPC stimulated PPI turnover in platelets with in situ manipulated levels of PPI; or in platelets from pathophysiological states. AGEPC is emerging as a potent mediator (autacoid). PPI turnover is drawing support for being a cell signalling event. How this signal-mechanism is involved in biochemical mode of action of this new mediator (AGEPC) is therefore an important issue. This will be explored using platelets as a model cell.