Zweng T N, Lynch M J, Bove E L, Fox M H, Iannettoni M D, Bolling S F, Gallagher K P
Department of Surgery, University of Michigan Medical School, Ann Arbor.
J Thorac Cardiovasc Surg. 1991 Feb;101(2):326-36.
The objective of this study was to determine the effect of oxygen and the oxygen radical-scavenging enzyme catalase on the neonatal rabbit heart exposed to global ischemia. The experiments were performed with an isolated neonatal (7 to 10 days of age) working heart model in which normothermic (37 degrees C) ischemia was produced for 60 minutes. Left ventricular developed pressure, ratio of change of ventricular pressure to change in time, and aortic flow were measured before ischemia and 30 minutes after reperfusing the hearts with physiologic saline solution. In the control group (ischemia only), developed pressure and ratio of change of ventricular pressure to change in time recovered to 27% +/- 3% (mean +/- standard error of the mean) and 24% +/- 7% of baseline; the hearts were incapable of ejecting (aortic flow = 0). Treatment of hearts before and after ischemia with catalase (150 units/ml of perfusate) was studied in a second group (control plus catalase), but functional recovery (developed pressure = 32% +/- 1%; ratio of change of ventricular pressure to change in time = 24% +/- 2%, and aortic flow = 0) was not significantly different from the control group. The effect of washout midway through the ischemic period with a low oxygen (oxygen concentration less than 35 mm Hg) solution was measured in a third group (hypoxic physiologic saline solution). Functional recovery (developed pressure = 13% +/- 3%; ratio of change of ventricular su pressure to change in time = 13% + 2%; aortic flow = 0) was not significantly different from the control and control plus catalase groups. In marked contrast were the effects of washout with an oxygenated (oxygen concentration greater than 500 mm Hg) solution (oxygenated physiologic saline solution) in which functional recovery (developed pressure = 78% +/- 3%; ratio of change of ventricular pressure to change in time = 80% +/- 3%; aortic flow = 39% +/- 9%) was significantly better than in the control, control plus catalase, and hypoxic physiologic saline solution groups. Use of modified St. Thomas' Hospital cardioplegic solution (cardioplegic solution group) during the ischemic period also resulted in substantial functional recovery (developed pressure = 80% +/- 3%; ratio of change of ventricular pressure to change in time = 78% +/- 5%; aortic flow = 64% +/- 7%) that did not differ significantly from that in the oxygenated physiologic saline solution group.(ABSTRACT TRUNCATED AT 400 WORDS)
本研究的目的是确定氧气和氧自由基清除酶过氧化氢酶对暴露于全脑缺血的新生兔心脏的影响。实验采用离体新生（7至10日龄）工作心脏模型，在该模型中产生常温（37℃）缺血60分钟。在缺血前以及用生理盐水溶液对心脏进行再灌注后30分钟，测量左心室舒张末压、心室压力变化与时间变化的比值以及主动脉血流量。在对照组（仅缺血）中，舒张末压和心室压力变化与时间变化的比值恢复到基线的27%±3%（平均值±平均标准误差）和24%±7%；心脏无法射血（主动脉血流量 = 0）。在第二组（对照组加过氧化氢酶）中研究了在缺血前后用过氧化氢酶（150单位/毫升灌注液）处理心脏的情况，但功能恢复（舒张末压 = 32%±1%；心室压力变化与时间变化的比值 = 24%±2%，主动脉血流量 = 0）与对照组无显著差异。在第三组（低氧生理盐水溶液组）中测量了在缺血期中途用低氧（氧浓度低于35毫米汞柱）溶液冲洗的效果。功能恢复（舒张末压 = 13%±3%；心室压力变化与时间变化的比值 = 13% + 2%；主动脉血流量 = 0）与对照组和对照组加过氧化氢酶组无显著差异。与之形成鲜明对比的是，用含氧（氧浓度高于500毫米汞柱）溶液（含氧生理盐水溶液）冲洗的效果，其功能恢复（舒张末压 = 78%±3%；心室压力变化与时间变化的比值 = 80%±3%；主动脉血流量 = 39%±9%）明显优于对照组、对照组加过氧化氢酶组和低氧生理盐水溶液组。在缺血期使用改良的圣托马斯医院心脏停搏液（心脏停搏液组）也导致了显著的功能恢复（舒张末压 = 80%±3%；心室压力变化与时间变化的比值 = 78%±5%；主动脉血流量 = 64%±7%），与含氧生理盐水溶液组无显著差异。（摘要截选至400字）
