摘要
实验旨在观察在体大鼠短暂缺血后心肌膜ＡＴＰ酶活性的变化及粉防己碱（Ｔｅｔ）的作用。分离缺血１５ｍｉｎ、再灌注２ｈ后及在缺血再灌注前给Ｔｅｔ的大鼠心肌粗制质膜和内质网，测定质膜Ｎａ＋－Ｋ＋－ＡＴＰ酶和内质网Ｃａ２＋－ＡＴＰ酶活性。结果表明，心肌缺血１５ｍｉｎ后二酶活性均明显降低，分别为假结扎组的６３．６％和７２．６％（Ｐ＜０．０１），再灌注后Ｎａ＋－Ｋ＋－ＡＴＰ酶活性有所恢复，再灌注３０ｍｉｎ时为假结扎组的７２．１％（Ｐ＜０．０１），而Ｃａ２＋－ＡＴＰ酶活性则进一步下降，再灌注３０ｍｉｎ时为假结扎组的５０．４％（Ｐ＜０．０１），再灌注后２ｈ二酶活性分别升高至假结扎组的８０．９％和６５．３％（Ｐ＜０．０１）。在缺血前２０ｍｉｎ分别给予Ｔｅｔ６４．２和９６．３μｍｏｌ／ｋｇ及硝苯啶（０．２３μｍｏｌ／ｋｇ），能明显减少内质网Ｃａ２＋－ＡＴＰ酶活性的降低。结果提示心肌膜ＡＴＰ酶活性的降低可能参与了短暂心肌缺血所致再灌注损伤的发生机制，Ｔｅｔ可减少缺血和／或再灌注时内质网Ｃａ２＋－ＡＴＰ酶活性降低。
? To investigate the changes of myocardial ATPase activity and the effect of tetrandrine on ATPase activity the rough sarcolemma and sarcoplasmic reticulum of myocardium underwent 15 min of ischemia plus 2h of reperfusion and administrated tetrandrine(IP)20 min before ischemia were isolated in rats.The sarcolemma Na+K+ATPase activity and sarcoplasmic reticulum Ca2+ATPase activity were assayed,respectively.The results showed both ATPase activity redueced significantly (63.6% and 72.6% of shamocclusion group after 15 min of ischemia ,respectively(P<0.01). After reperfusion,Na+K+ATPase activity recovered to some extent.At 30 min after reperfuison the activity was 72.1% of the shamocclusion group.However,the Ca2+ATPase activity decreased further.At 30min after reperfusion the activity was 50.4% of the sham occlusion group(P<0.01).After 2h reperfusion the activities were 80.9% and 65.3% of shamocclusion group,respectively(P<0.01).Administration of tetrandrine(64.2 and 96.3μ mol/kg) and nifedipine (0.23μ mol/kg)20 min before ischemia could attenuate the decrease of sarcoplasmic reticulum Ca2+ATPase activity.These results suggest that the decrease of myocardial ATPase activity might be involved in the pathogenesis of transient ischemiainduced myocardial reperfusion injury and tetrandrine might attenuate the decrease of sarcoplasmic reticulum Ca2+ATPase activity during ischemia and/or reperfusion. KEY WORDS myocardial reperfusion injury; ATPase tetrandrinePPAGESS CHANGES IN PROPORTION OF MUSCLE FIBER TYPES IN RAT DIAPHRAGM IN RESPONSE TO CHRONIC HYPOXIA$$$$Wang Donglin, Mao Baoling, Qian Guisheng, Guo xianjian, Gao Guangzheng(Institute of Respiratory Medicine ,Xinqiao Hospital, Chongqing 630037)ABSTRACT The adaptive changes in proportion of muscle fiber types,which were indentified by histochemistry,in rat costal and crural diaphragm (DⅠcos and DⅠcru)compared with hindlimb muscles after exposure to nomobaric hypoxia (10% O2)or simulated hypobaric hypoxia (5000 m above sea level) for one or three months were observed.The results showed that there was a tendency of transformation in muscle fiber types from glycolytic (ⅡB) to oxidative (ⅡA) fibers in both DⅠcos and DⅠcru.The changes in DⅠcos were earlier and more significant than that in DⅠcru and hindlimb muscles observed.The results indicated that the effect of chronic hypoxia on muscles may be different according to their functional demand.
出处
《中国应用生理学杂志》
CAS
CSCD
1998年第1期30-33,共4页
Chinese Journal of Applied Physiology
基金
国家自然基金
