8％─9％和12％─13％低氧气体诱导大鼠左右心室肌自由基增殖  

8%-9% AND 12% 13% HYPOXIC GAS INDUCED FREE RADICALS GENERATION IN RAT'S LEFT AND RIGHT MYOCARDIUM

作　　者：韩沾元[1] 陈铭[1] 闻萍[1] 王庆华[1] 

机构地区：[1]中国科学院上海生理研究所,上海医药工业研究院制剂研究室

出　　处：《生理学报》1995年第5期453-462,共10页Acta Physiologica Sinica

基　　金：中国科学院上海生理研究所低氧生理开放实验室资助

摘　　要：α－苯基－Ｎ－叔了基甲亚胺－Ｎ－氧化物（ＰＢＮ，α－ｐｈｅｎｙｌ－ｔｅｒｔ－ｂｕｔｙｌｎｉｔｒｏｎｅ）由股静脉注入ＳＤ大鼠体内，鼠暴露于８％—９％Ｏ２（ｉｎＮ２）１５ｍｉｎ，左心肌ＰＢＮ－自旋加合物电子自旋共振（ＥＳＲ，ｅｌｅｃｔｒｏｎｓｐｉｎｒｅｓｏｎａｎｃｅ）信号明显增强（与常氧组比，ｎ＝５，Ｐ＜０．０５），而右心肌变化不明显（ｎ＝５，Ｐ＞０．０５）。暴露于１２％—１３％Ｏ２（ｉｎＮ２）的鼠分四组：Ⅰ（低氧１５ｍｉｎ）、Ⅱ（低氧６０ｍｉｎ）、Ⅲ（低氧３０ｍｉｎ／常氧１５ｍｉｎ／低氧３０ｍｉｎ）和Ⅳ（低氧前由股静脉注入ＭＰＥＧ－ＳＯＤ后低氧６０ｍｉｎ）。Ⅱ组左右心肌ＰＢＮ－自旋加合物ＥＳＲ信号增强十分明显（与常氧组比，ｎ＝５，Ｐ＜０．０１），但在Ⅰ组变化不明显（与常氧组比，ｎ＝５，Ｐ＞０．０５）。Ⅲ组右心肌ＰＢＮ－自旋加合物ＥＳＲ信号明显下降（与Ⅱ组比，ｎ＝５，Ｐ＜０．０５），而左心肌下降不明显。Ⅳ组左心肌ＰＢＮ－自旋加合物ＥＳＲ信号明显下降（与Ⅱ组比，ｎ＝５，Ｐ＜０．０５），而右心肌下降不明显。鼠暴露于８％—９％Ｏ２（ｉｎＮ２）１５ｍｉｎ和１２％—１３％Ｏ２（ｉｎＮ２）６０ｍｉｎ期间，左右心肌中超氧化物?Alpha-phenyl-tert-butylnitrone (PBN) was administered intravenously to capture free radicals of rat's myocardium. Rats were exposed to hypoxic gas (8% 9% O2 in N2) for 15min. The ESR (electron spin resonance) signal intensity of PBN-spin adduct in the left myocardium increased significantly as compared with the normoxia group (n=5, P<0. 05), but in the right myocardium there was no significant changes between hypoxia and normoxia. Rats exposed to hypoxic gas (12%-13 % O2 in N2) were divided into four groups: Ⅰ(hypoxia for 15 min), Ⅱ(hypoxia for 60 min),Ⅲ (hypoxia for 30 min/normoxia for 15 min/hypoxia for 30 min) and Ⅳ (injected MPEG-SOD intravenously before hypoxia for 60 min). The ESR signal intensity of PBN-spin adduct of left and right myocardium in group Ⅱ increased significantly as compared with normoxia group (n= 5, P< 0. 01), but the ESR signal intensity of groupⅠ didn't show obvious change as compared with normoxia group (n=5, P>0. 05). In the right myocardium of group Ⅲ the ESR signal intensity of PBN-spin adduct decreased significantly as compared with group Ⅱ (n=5, P<0. 05) and in the left myocardium did not decrease evidently. In the left myocardium of group Ⅳ the ESR signal intensity of PBN-spin adduct decreaseed evidently as compared with group 11 (n=5, P<0. 05) and that in the right myocardium did not decrease evidently.When the rats were exposed to 8%-9% hypoxic gas for 15 min and 12%-13 % hypoxic gas for 60 min, the SOD (superoxide dismutase, EC 1. 11. 1. 9) activity of myocardium decreased and the content of MDA (malondialdehyde) increased significantly (n=8, P<0. 05 or P<0.01). The above results suggested that one way of myocardium free radical gereration may be relevant to decrease of SOD activity. The generation of free radicals pertained chiefly to superoxide free radical in the left myocardium and the membrane structure of myocardium cells might have been damaged largely during hypoxia.

关 键 词：低氧 心肌 自由基 高海拔 

分 类 号：Q494[生物学—生理学] R339.54[医药卫生—人体生理学]