角叉菜诱导大鼠胸膜炎中环氧酶-2的生成及NS-398对其选择性抑制作用

目的：检测角叉菜诱导的大鼠胸膜炎渗出细胞中COX-2的存在并观察NS-398对其活性的影响。方法：用SDS-PAGE和Western blot分析及PGHS-1和PGHS-2抗血清，识别并检测胸膜炎渗出细胞中的COX-2。酶活性用TLC法测定。结果：致炎后5 h, PGHS-2出现, 19 h时消失，而PGHS-1在注射角叉菜前后均出现。此外，在胸膜炎大鼠和正常大鼠的肺、胃、肾微粒体中，只检测到PGHS-1, 未检测到PGHS-2。新的非甾体抗炎药NS-398,可明显抑制COX-2活性（IC₅₀=4.5 μmol.L^-1 ）。 结论：COX-2仅存在于角叉菜诱导的炎症部位；NS-398可选择性抑制COX-2，并呈剂量依赖性。

INDUCTION OF CYCLOOXYGENASE-2 IN RAT CARRAGEENIN-INDUCED PLEURISY AND ITS SELECTIVE INHIBITION BY NS-398

AIM: To detect cyclooxygenase-2(COX-2)/prostaglandin H synthase-2(PGHS-2) in cells of pleural exudate and investigate the effect of NS-398 on its activity. METHODS: COX-2 was tested by SDS-PAGE and Western blot in cells of the pleural exudate induced in rats by intrapleural injection of 0.2 ml of 2% carrageenin. TLC was used to analyze the activity of COX-2. RESULTS: The examination using PGHS-1 or PGHS-2 antiserum showed that PGHS-2 appeared at the 5th hour after carrageenin injection, and vanished at the 19th hour. While, PGHS-1 appeared in cells before and after carrageenin injection. Furthermore, only PGHS-1, but not PGHS-2, was detected in the microsomal fraction of the lung, stomach and kidney of pleurisy-affected and normal control rats. NS-398, a novel nonsteroidal anti-inflammatory agent, suppressed the activity of COX-2 with IC₅₀=4.5　μmol.L^-1. CONCLUSION: COX-2 is only present in inflammatory site induced by carrageenin. NS-398 may selectively inhibit COX-2 activity in a dose-dependent manner.