Chopp M, Welch K M, Tidwell C D, Knight R, Helpern J A
Department of Neurology, Henry Ford Hospital, Detroit, MI 48202.
Stroke. 1988 Dec;19(12):1521-5. doi: 10.1161/01.str.19.12.1521.
We investigated the effect of mild whole-body hyperthermia before and after 16 minutes of global cerebral ischemia on metabolic recovery during recirculation in cats using in vivo phosphorus-31 nuclear magnetic resonance spectroscopy. Hyperthermia (temperature 40.6 +/- 0.2 degrees C) was induced greater than or equal to 1 hour before ischemia and was maintained during 1.5-2 hours of recirculation in nine cats; four cats were subjected to hyperthermia without cerebral ischemia, six to hyperthermia during recirculation (after return of intracellular pH to preischemic values), and 14 to normothermic ischemia and recirculation. Our data indicate that preischemic hyperthermia results in an intracellular cerebral pH during recirculation significantly lower than that in normothermic cats. In hyperthermic cats beta-ATP and phosphocreatine (PCr) concentrations and the ratio of PCr to inorganic phosphate failed to return to preischemic levels during recirculation in contrast to normothermic cats. Hyperthermia without ischemia and hyperthermia during recirculation had no significant effect on intracellular pH. Thus, preischemic hyperthermia has a detrimental effect on metabolic recovery after transient global cerebral ischemia.
我们使用体内磷-31核磁共振波谱法，研究了猫全脑缺血16分钟前后轻度全身热疗对再灌注期间代谢恢复的影响。在9只猫中，热疗（温度40.6±0.2摄氏度）在缺血前1小时或更长时间诱导，并在1.5 - 2小时的再灌注期间维持；4只猫在无脑缺血情况下进行热疗，6只猫在再灌注期间（细胞内pH值恢复到缺血前值后）进行热疗，14只猫进行正常体温的缺血和再灌注。我们的数据表明，缺血前热疗导致再灌注期间细胞内脑pH值显著低于正常体温的猫。与正常体温的猫相比，热疗猫的β-ATP和磷酸肌酸（PCr）浓度以及PCr与无机磷酸盐的比率在再灌注期间未能恢复到缺血前水平。无缺血热疗和再灌注期间热疗对细胞内pH值无显著影响。因此，缺血前热疗对短暂全脑缺血后的代谢恢复有不利影响。
