Tosaki A, Cordis G A, Szerdahelyi P, Engelman R M, Das D K
University of Connecticut Health Center, Farmington 06030-1110.
J Cardiovasc Pharmacol. 1994 Mar;23(3):365-73.
The effects of preconditioning on development of reperfusion-induced ventricular fibrillation (VF), ventricular tachycardia (VT), free radical formation, and ion shifts, particularly those of Na, K, Ca, and Mg, were studied in isolated rat heart. Hearts were randomly divided into four groups: group I, aerobically perfused time-matched controls with no preconditioning or ischemia; group II, hearts subjected to 30-min global ischemia followed by 30-min reperfusion; group III, hearts subjected to one cycle of preconditioning, consisting of 5-min global ischemia plus 10-min reperfusion, followed by 30-min global ischemia plus 30-min reperfusion; and group IV, hearts subjected to four cycles of preconditioning (5-min ischemia plus 10-min reperfusion) followed by 30-min ischemia plus 30-min reperfusion. The incidences of VF and VT were reduced from their nonpreconditioned ischemic values of 100 and 100% in group II to 83 and 92% in group III and to 33% (p < 0.05) and 41% (p < 0.05) in group IV, respectively. Maximum malondialdehyde formation, as an indirect marker of free radicals, was observed after 30-min ischemia followed by 10-min reperfusion (0.72 +/- 0.1 nmol/ml) in the nonpreconditioned ischemic group (protocol II). One and four cycles of preconditioning reduced formation of malondialdehyde from the nonpreconditioned ischemic value of 0.72 +/- 0.1 to 0.35 +/- 0.02 and 0.26 +/- 0.02 nmol/ml (p < 0.05), respectively. The same trend was observed when free radical formation was directly detected by salicylic acid.(ABSTRACT TRUNCATED AT 250 WORDS)
在离体大鼠心脏中研究了预处理对再灌注诱导的心室颤动（VF）、室性心动过速（VT）、自由基形成和离子转移（特别是钠、钾、钙和镁离子转移）的影响。心脏被随机分为四组：第一组，进行有氧灌注、时间匹配的对照组，未进行预处理或缺血；第二组，心脏经历30分钟全心缺血，随后进行30分钟再灌注；第三组，心脏经历一个预处理周期，包括5分钟全心缺血加10分钟再灌注，随后进行30分钟全心缺血加30分钟再灌注；第四组，心脏经历四个预处理周期（5分钟缺血加10分钟再灌注），随后进行30分钟缺血加30分钟再灌注。VF和VT的发生率从第二组未预处理缺血时的100%和100%分别降至第三组的83%和92%，以及第四组的33%（p<0.05）和41%（p<0.05）。在未预处理的缺血组（方案II）中，30分钟缺血后10分钟再灌注时观察到作为自由基间接标志物的丙二醛形成最大值（0.72±0.1 nmol/ml）。一个和四个预处理周期分别将丙二醛形成量从未预处理缺血时的0.72±0.1降至0.35±0.02和0.26±0.02 nmol/ml（p<0.05）。当用水杨酸直接检测自由基形成时也观察到相同趋势。（摘要截短于250字）
