黏膜肥大细胞脱颗粒和自由基生成在大鼠肠缺血再灌注损伤中的作用

The role of mucosal mast cell degranulation and free-radical generation in intestinal ischaemia-reperfusion injury in rats.

作者信息

Kimura T, Fujiyama Y, Sasaki M, Andoh A, Fukuda M, Nakajima S, Bamba T

机构信息

Department of Internal Medicine, Shiga University of Medical Science, Tukinowa, Otsu, Japan.

出版信息

Eur J Gastroenterol Hepatol. 1998 Aug;10(8):659-66.

PMID:9744694

Abstract

OBJECTIVES

In this study, we determined the role of mucosal mast cell (MMC) activation in the pathogenesis of intestinal ischaemia-reperfusion (I/R) injury by immunohistochemical analysis using anti-RMCP II antibody. In addition, we investigated the role of free-radical generation in the activation of MMCs in this model.

METHODS

In the first experiment, rats were divided into four groups: (1) sham operated; (2) I/R + saline; (3) I/R + the mast cell stabilizer, MAR-99 (30 mg/kg); and (4) I/R + MAR-99 (100 mg/kg). Treatment with MAR-99 was started 1 h before the occlusion of the superior mesenteric artery (SMA). In the second experiment, rats were divided into five groups: (1) sham operated; (2) I/R + saline; (3) I/R + superoxide dismutase (SOD; 50,000 U/ml); (4) I/R + catalase (90,000 U/ml); and (5) I/R + allopurinol (50 mg/kg/day). Intravenous administration of SOD and catalase was performed 1 h before SMA occlusion. Oral administration of allopurinol was started 2 days before I/R surgery. We measured several parameters of intestinal mucosal injury and evaluated the degranulation of MMCs by using an immunohistochemical technique.

RESULTS

The number of resting MMCs, detected by anti-RMCP II antibody, was significantly decreased in the I/R-treated rats. The I/R treatment induced a decrease in the mucosal histamine content and an increase in plasma histamine levels. Mucosal permeability in the small intestine was significantly enhanced by I/R treatment. However, these changes were significantly prevented by pretreatment with the MMC stabilizer, MAR-99. Furthermore, administration of several free-radicals scavengers (SOD, catalase, and allopurinol) also blocked the I/R-induced degranulation of MMCs.

CONCLUSION

These data indicate that activation of MMCs was involved in the pathogenesis of I/R-induced intestinal mucosal injury. In addition, some parts of the I/R-induced MMC activation pathway were mediated by free-radical generation.

摘要

目的

在本研究中，我们通过使用抗RMCP II抗体的免疫组织化学分析，确定黏膜肥大细胞（MMC）激活在肠缺血再灌注（I/R）损伤发病机制中的作用。此外，我们研究了自由基生成在该模型中MMC激活中的作用。

方法

在第一个实验中，将大鼠分为四组：（1）假手术组；（2）I/R + 生理盐水组；（3）I/R + 肥大细胞稳定剂MAR-99（30 mg/kg）组；（4）I/R + MAR-99（100 mg/kg）组。在肠系膜上动脉（SMA）闭塞前1小时开始用MAR-99治疗。在第二个实验中，将大鼠分为五组：（1）假手术组；（2）I/R + 生理盐水组；（3）I/R + 超氧化物歧化酶（SOD；50,000 U/ml）组；（4）I/R + 过氧化氢酶（90,000 U/ml）组；（5）I/R + 别嘌呤醇（50 mg/kg/天）组。在SMA闭塞前1小时静脉注射SOD和过氧化氢酶。在I/R手术前2天开始口服别嘌呤醇。我们测量了肠黏膜损伤的几个参数，并使用免疫组织化学技术评估了MMC的脱颗粒情况。

结果

通过抗RMCP II抗体检测到，I/R处理的大鼠中静息MMC的数量显著减少。I/R处理导致黏膜组胺含量降低，血浆组胺水平升高。I/R处理显著增强了小肠黏膜通透性。然而，用MMC稳定剂MAR-99预处理可显著预防这些变化。此外，给予几种自由基清除剂（SOD、过氧化氢酶和别嘌呤醇）也可阻断I/R诱导的MMC脱颗粒。