大鼠严重烧伤早期心肌细胞膜阴离子位点改变的研究

Changes of anionic sites on myocardial cell membrane in the early stage after severe burns in rats

目的：探讨严重烧伤后早期心肌细胞膜结构损伤的分子病理学基础。方法：以聚乙烯亚胺（ＰＥＩ）为阳离子探针，运用透射电镜观察大鼠严重烧伤早期心肌细胞膜基板阴离子位点的变化，并进行心肌硝酸镧示踪观察，同时测定心肌组织含水量变化。结果：正常心肌细胞表面ＰＥＩ颗粒沿基膜外呈较规则的点阵式、线性排列分布。烧伤后１ｈＰＥＩ颗粒已开始有所减少，烧伤后６ｈＰＥＩ颗粒进一步减少，并可见心肌细胞基膜与质膜分离，基膜缺损或质膜断裂。伤后１ｈ镧颗粒穿过心肌细胞膜进入细胞内。伤后３ｈ心肌组织含水量增加（Ｐ＜０．０１）。结论：证实严重烧伤后早期心肌细胞膜基板阴离子位点减少可导致肌膜通透性增加，心肌组织水肿加剧，膜保护屏障功能下降。

Objective: To acquire more understanding about the myocardial cell membrane structural damage during severe burns on the molecular level. Methods: In the in vivo burn model established in rats, alterations of the anion sites at basal lamina of the myocardial cells was assessed with a PEI cationic probe. The membrane permeability of the myocardial cells was observed using colloidal lanthanum as a marker and the myocardial water content measured. Results: The anion sites of basal lamina of the myocardial cells showed regular linear lattice arrangement (40～80 mm). The PEI granules of the basal lamina were decreased at the 1st h and decreased significantly at the 6th h after burns. The lanthanum granules entered into the myocardial cells at the 1st h and the myocardial water content was significantly increased (P<0.01)at the 3rd h after burns. Conclusion: The damage of the basal lamina and decrease of the anion sites on the myocardial cells might be a contributive factor causing the increase of membrane permeability, tissue edema and membrane protective barrier dysfunction after severe burns