+GZ应激对麻醉犬内皮细胞结构与功能的影响

目的探讨＋ＧＺ应激对内皮细胞的结构及其功能的影响。方法１２只麻醉犬分为两组：实验组（ｎ＝９）和对照组（ｎ＝３）。实验组均经受从＋１ＧＺ到＋９ＧＺ作用（＋１、＋３、＋５、＋７和＋９ＧＺ分别作用６０ｓ，每次间隔２０ｍｉｎ）。取每次＋ＧＺ作用前后１ｍｉｎ动脉血以观察血浆中内皮素－１（ＥＴ－１）含量的变化，同时在＋９ＧＺ作用后取心肌组织（包括左、右心房及左心室）观察局部组织中ＥＴ－１含量的改变。并在光镜、电镜下观察＋ＧＺ应激后心血管系统内皮细胞结构的变化。对照组不经受＋ＧＺ作用。结果＋７ＧＺ和＋９ＧＺ后血浆ＥＴ－１含量明显高于＋１ＧＺ作用前水平（Ｐ＜０．０５）；心肌组织中ＥＴ－１的含量也有增高的趋势，但与对照组相比无显著性差异。光镜、电镜结果显示，内皮细胞出现严重的变性改变，但无明显的坏死。结论高＋ＧＺ应激和（或）＋ＧＺ重复暴露可引起内皮细胞分泌ＥＴ－１的增加；并可导致麻醉犬心血管内皮细胞结构的损害。内皮细胞的受损可能与＋ＧＺ应激后的心血管功能改变有关。

Effects of GZ stress on endothelial cell in anesthetized dog

Objective The purpose of this study was to investigate the effects of GZ stress on structure and function of endothelial cells. Methods Twelve dogs were divided into 2 groups: experimental group (n=9) and control group (n=3). The experimentals underwent GZ exposure from 1 GZ to 9 GZ for 5 min (experiencing 1, 3, 5, 7 and 9 GZ for 60 s respectively, with 20 min interval). After that, endothelial cells of right atrium were observed by light and electron microscope. Controls did not undergo any Gz stress. ResultsTBZ Plasma concentrations of ET1 in experimentals following 7 GZ and 9 Gz exposure were significantly higher than that in control group. Microscopic observation showed that endothelial cells in experimentals had serious degenerative change, but no obvious necrosis. Conclusions High GZ may induce increase of ET1 secretion and histological change of endothelial cells. It was suggested that the changes of endothelial cells may take part in the dysfunction of cardiovascular system after GZ stress.