Chen K, Inoue M, Okada A
Department of Pediatric Surgery, Osaka University Medical School, Japan.
Biochem Biophys Res Commun. 1996 Jul 25;224(3):703-8. doi: 10.1006/bbrc.1996.1087.
Nitric oxide (NO) production is increased in the intestine and may contribute to intestinal injury in sepsis. However, the tissue expression of inducible NO synthase (iNOS) mRNA throughout the digestive tract and its relation with the mucosal damage after endotoxin challenge remain unknown. We therefore measured tissue expression of mRNA encoding iNOS by Northern blot analysis and reverse transcription PCR. The iNOS mRNA was detectable at 1 h, peaked at 4 h, and remained faint at 24 h after endotoxin injection in esophagus, duodenum, jejunum, ileum, and colon, but not in the stomach. Pre-treatment with dexamethasone attenuated the rise of iNOS mRNA. Both dexamethasone and NOS inhibitor, L-NAME, ameliorated the endotoxin-induced increase in intestinal mucosal permeability. Our results indicate that there is tissue-specific expression of iNOS mRNA in the digestive tract. The manipulations that decrease NO production may have therapeutic potential in preserving intestinal mucosal integrity in sepsis.
脓毒症时肠道一氧化氮（NO）生成增加，可能导致肠道损伤。然而，诱导型一氧化氮合酶（iNOS）mRNA在整个消化道的组织表达及其与内毒素攻击后黏膜损伤的关系尚不清楚。因此，我们通过Northern印迹分析和逆转录PCR测定了编码iNOS的mRNA的组织表达。内毒素注射后1小时在食管、十二指肠、空肠、回肠和结肠中可检测到iNOS mRNA，4小时达到峰值，24小时时仍较微弱，但在胃中未检测到。地塞米松预处理可减弱iNOS mRNA的升高。地塞米松和一氧化氮合酶抑制剂L-NAME均可改善内毒素诱导的肠道黏膜通透性增加。我们的结果表明，iNOS mRNA在消化道存在组织特异性表达。减少NO生成的干预措施可能对脓毒症时保护肠道黏膜完整性具有治疗潜力。
