MPG静注减轻清醒狗缺血后心肌顿抑

为了解自由基清除剂２巯基丙酰基甘氨酸（ＭＰＧ）能否减轻缺血后心肌顿抑，本文报告了在清醒狗模型中氧自由基清除剂ＭＰＧ对缺血后心肌顿抑的疗效。３９只清醒狗模型阻闭前降支１５ｍｉｎ后再灌注４８ｈ。治疗组（ｎ＝１７）于阻闭前１５ｍｉｎ始静脉给予ＭＰＧ（１００ｍｇ／ｋｇ·ｈ），共持续６０ｍｉｎ，对照组（ｎ＝２２）给予生理盐水。结果表明，二组缺血区侧支血流、缺血区大小及血液动力学指标无显著差异，而治疗组室壁收缩增厚指数（一种局部心肌功能指标）于再灌注后２、３、４、５、６ｈ明显大于对照组，当侧支血流低于１０％时，改善更明显。指数回归分析结果显示，治疗组侧支血流越低，收缩功能恢复程度越明显。结论，ＭＰＧ可以促进缺血后心肌顿抑的恢复，这种有益的疗效在低侧支血流时更明显。

N 2 MERCAPTOPROPIONYL-GLYCINE IMPROVES RECOVERY OF MYOCARDIAL STUNNING AFTER REVERSIBLE REGIONAL ISCHEMIA IN CONSCIOUS DOGS

In order to investigate the therapeutic effect of N-2-Mercaptopropionyl-glycine (MPG), a scavenger of hydroxyl radical, on postischemic myocardial dysfunction of 39 conscious unsedated dogs were undergone a 15 min occlusion of left anterior descending coronary artery followed by 48 hours of reperfusion. The treated dogs (n = 17) received an infusion of MPG (100 mg/kg.h) for 60 minutes (starting 15 minutes before occlusion) while the control dogs (n = 22) received normal saline. The result showed that there were no significant differences between the two groups in collateral blood flow determined by radioactive microsphere, occlusion vascular bed and hemodynamic variables. Systolic thickening fraction of ventricular wall (an index of regional myocardial function) was similar in both groups under baseline condition and during ischemia, whereas it (expressed as percent of baseline) was considerably greater in treated dogs at 2, 3, 4, 5, 6 hours of reperfusion. Much more significant recovery was observed in the dogs with collateral flow less than 10% in MPG group. The exponential regression analysis showed that the lower the collateral flow, the greater the recovery of function in treated dogs. It is concluded that MPG improves recovery of myocardial function after reversible regional ischemia, especially with lower collateral blood flow.