摘要
目的观察重复高 +Gz暴露后大鼠心肌几种酶活性的变化特点和低G预适应与茶多酚 (TP)的防护效果。方法 3 2只雄性Wistar大鼠随机分成 4组 (每组 8只 ) :对照组 (A组 ) ;+1 0Gz组 (B组 ) ;低G预适应组 (C组 ) ;TP防护组 (D组 )。B、C、D组重复高G暴露 (+1 0Gz 3 0s ,5次 /d ,3d/wk ,3wk) ,A组仅受 +1Gz作用 ;C组于 +1 0Gz暴露前约 1h受 +2Gz作用 5min ;D组于暴露前约 1h灌胃给予TP(2 0 0mg/kg) ,而A、B、C组给予等量蒸馏水。各组均于末次 +Gz作用后次日处死大鼠 ,速取心脏制成冰冻切片 ,对酸性磷酸酶 (ACP)、琥珀酸脱氢酶 (SDH)、细胞色素氧化酶 (Cytaa3)和三磷酸腺苷酶 (ATPase)进行组织化学染色和图象分析。结果与A组相比 ,B组ACP和SDH活性均明显下降 (P <0 .0 5 ) ,Cytaa3有下降趋势 ,各组间ATPase活性无差异 ;而低G预适应和TP对重复高 +Gz暴露引起的酶活性下降具有保护作用。结论重复高 +Gz暴露可引起心肌溶酶体的标志酶ACP和线粒体内膜的标志酶SDH活性降低 ,提示心肌组织氧化代谢功能下降 ;而低G预适应和天然抗氧化药物TP具有一定的保护作用。
Objective To determine the changes of several myocardial enzymes in rats after repeated high +Gz exposure and the protective effects of preconditioning of low G exposure and tea polyphenols(TP). Method Thirty two male Wistar rats were randomly divided into 4 groups(n=8 each):control group(group A),+10 Gz group(group B),low G preconditioning group(group C) and TP protection group(group D).Group B,C and D were exposed to repeated +10 Gz stress (each for 30 s,5 times/d with +1 Gz 1 min intervals,3 d/wk,3 weeks in total),but group A was only submitted to +1 Gz for 5 min. Group C was exposed to +2 Gz for 5 min about 1 h prior to +10 Gz stress. Additionally, TP(200 mg/kg) was given orally to group D about 1h prior to the +Gz experiment, while distilled water was given to groups A,B and C instead. On the next day after the last centrifuge run,the hearts were taken out immediately for making frozen tissue sections.Enzyme histochemical staining and image analysis were carried out for acid phosphatase(ACP),succinate dehydrogenase(SDH),cytochromeoxidase(Cyt aa 3) and adenosine triphosphatase (ATPase). Result As compared with the control,the activities of ACP and SDH in +10 Gz stressed rats decreased significantly (P<0.05),and there was a declining trend for Cyt aa 3.But,low G preconditioning and TP had protective effects on +10 Gz stress induced reduction of these enzymatic activities (P<0.05). Conclusion The results showed that repeated high +Gz exposure could bring about decreases of activities in ACP(the marker enzyme of lysosome) and SDH(the marker enzyme of mitochondrial endomembrane),which indicated a reduction of oxidative metabolism in myocardial tissue;but preconditioning with low G and natural antioxidant TP had protective effects.
出处
《航天医学与医学工程》
CAS
CSCD
北大核心
2001年第6期410-413,共4页
Space Medicine & Medical Engineering
基金
全军医药卫生科研基金资助课题 ( 0 1MB0 5 1)
关键词
正加速度
心肌
酶活性
氧化代谢
抗氧化剂
预适应
Gz
myocardium
enzymes
oxidative metabolism
antioxidants
preconditioning
