Analysis of physiological and pathophysiological effects of platelet activating factor on the kidney.

血小板活化因子（PAF）被认为在各种肾小球疾病的发病机制中起重要作用。最近，PAF受体cDNA已被克隆。因此，本研究计划对PAF受体在肾脏中的表达进行研究，第一部分是mRNA表达分析。我们计划定量分析肾脏结构各部分的mRNA表达。然而，常规的方法如北方印迹、常规的RT-PCR或原位杂交都不足以达到这一目的。因此，我们开发了一种新的RT-PCR方法，它能够以一种非常简单和可靠的方式定量分析微量样品中的mRNA。目前，我们正在利用这种方法研究肾单位分布和PAF受体mRNA表达的调控。同时，我们还采用北方印迹法检测了PAF受体mRNA在系膜细胞中的表达。目前我们正在进行PAF受体的免疫组织化学研究，并尝试用微灌注法研究PAF对肾近端小管的生理作用。到目前为止，没有观察到PAF对近端肾小管转运的显著影响。

Platelet activating factor (PAF) is believed to play an important role in the pathogenesis of various types of glomerular diseases. Recently, PAF receptor cDNA has been cloned. So we have made a plan of investigating the regulation of PAF receptor expression in the kidney.First part of our scheme consisted of analysis of mRNA expression. We planned quantitative analysis of mRNA expression in each part of the kidney structure. However, odinary methods such as Northern blot, conventinal RT-PCR or in situ hybridization was not enough for that purpuse. So we have developed new protocol of RT-PCR, which enables quantitative analysis of mRNA in minute samples in a very simple and reliable way. Now we are investigating nephron distribution and regulation of PAF receptor mRNA expression using this method. In parallel with this study, we also examined the regulation PAF receptor mRNA expression in cultured mesangial cells using Northern blot analysis.Second part of our scheme was the study of PAF receptor protein using specific antibody. Now we are performing immunohistochemistry of PAF receptor in the kidney.We also tried physiological studies of PAF effect on the renal proximal tubules using microperfusion method. So far no significant effect of PAF on proximal tubular transport has been observed.