纳络酮对心肺复苏后犬血流动力学和心肌氧自由基的影响

目的：观察纳络酮(naloxone)对犬心跳骤停复苏后血流动力学和心肌氧自由基的影响。方法：体外电击诱发犬室颤，3min后复苏，18只犬随机分为3组，CPR组，NLX组，正常对照组，每组6只，采用Swan-Ganz漂浮导管监测复苏前和后6h的CO和PAWP。6h后取心肌组织，匀浆测SOD和MDA的活性。结果：CPR组的平均动脉压在复苏后4、6h低于正常对照组，而NLX组在复苏后2、4、6h高于CPR组，与正常对照组无差异。CO、CI、SV和LVSWI在心跳骤停前三组间无统计学差异，复苏成功后0～6hNLX组和CPR组的各指标均低于正常组，而NLX组的CO、CI、SV和LVSWI在复苏后l-6h高于CPR组。复苏后6hCPR组和NLX组心肌组织SOD活性则低于正常对照组，而MDA高于正常对照组，NLX组心肌组织MDA含量较CPR组降低，而SOD活力较CPR组升高。结论：诱发室颤犬复苏成功后存在心功能不全、氧自由基的产生和内源性抗氧化机制的削弱、NLX能予以改善。

Effects of Naloxone on the Hemodynamic and Activities of SOD and MDA in Postresuscitation Dog from Cardiac Arrest

Objective; To investigate the effects of naloxone on the hemodynamic status and activities of superoxide dismutase (SOD) and malonialdehyde (MDA) in postresuscitation dog from cardiac arrest. Method; 18 dogs were randomly divided into normal control group ( group N) , CPR group and naloxone group ( n = 6 ). Ventricular fibrillation (VF) was induced by external electricity, except for in group N. Cardiac output (CO) and pulmonary artery wedge pressure (PAWP) were measured in 18 dogs before and during a 6 - hour interval after successful resuscitation from 3 minutes VF. Having been finished the procedure, the heart was harvested and homogenized, then the activities of SOD and MDA level were measured. Results: The MAP of CPR group was lower than those of group N in 4 h and 6 hour after successful resuscitation. The MAP of NLX group were higher than those of CPR group 2,4 and 6 hours after successful resuscitation, and no significantly different with group N. The parameters of CO, CI, SV and LVSWI were not significantly different among three groups before prearrest. These parameters in CPR and NLX group were lower than those in group N after successful resuscitation. The CO,CI, SV and LVSWI of NLX group were higher than those of CPR group in 1 - 6 h after resuscitation. Compared with group N, both the activities of SOD in heart tissues of CPR group and NLX group were decreased while MDA level increased. However, Compared with CPR group, the activities of SOD in NLX group were significantly increased while the MDA level decreased. Conclusion; There is myocardial dysfunction in postresuscitation dog from cardiac arrest with oxygen free radical generation and the antioxidative enzyme acticity decreacing. Naloxone can improve these status.