Yoshida S, Busto R, Martinez E, Scheinberg P, Ginsberg M D
J Cereb Blood Flow Metab. 1985 Dec;5(4):490-501. doi: 10.1038/jcbfm.1985.75.
Levels of energy metabolites were measured in forebrain regions in fasted rats subjected to 4-h recirculation after 1 h of either incomplete or complete ischemia. Both models of ischemia were produced by a procedure combining bilateral common carotid artery occlusion, systemic hypotension, and CSF pressure elevation; the degree of intracranial hypertension was varied to produce incomplete and complete ischemia. Levels of brain lactate at the end of ischemia ranged from 16 to 19 mmol/kg in incomplete ischemia and from 11 to 13 mmol/kg in complete ischemia. Energy metabolism recovered evenly in the neocortical and subcortical regions with recirculation after incomplete ischemia. The metabolic recovery in the cerebral cortex after complete ischemia was similar to that observed after incomplete ischemia; however, recovery in the subcortical regions after complete ischemia was less extensive, NADH fluorescence remained high, and there was a fall in total creatine. Intracellular pH in the dorsal thalamus was more alkalotic after complete than incomplete ischemia. Thus, in the absence of profound tissue lactic acidosis, residual CBF during prolonged ischemia helps postischemic restitution of brain energy metabolism in subcortical regions. The pattern of poor recovery in these regions after complete ischemia suggests inadequate reperfusion. The decreased total creatine and the severe tissue alkalosis may be biochemical markers of advanced tissue injury during reflow.
在禁食大鼠中，于不完全或完全缺血1小时后进行4小时再循环，测量前脑区域的能量代谢物水平。两种缺血模型均通过双侧颈总动脉闭塞、全身性低血压和脑脊液压力升高的联合操作产生；通过改变颅内高压程度来产生不完全和完全缺血。不完全缺血时缺血结束时脑乳酸水平为16至19 mmol/kg，完全缺血时为11至13 mmol/kg。不完全缺血后再循环时，新皮质和皮质下区域的能量代谢均匀恢复。完全缺血后大脑皮质的代谢恢复与不完全缺血后观察到的相似；然而，完全缺血后皮质下区域的恢复程度较小，NADH荧光仍很高，总肌酸下降。完全缺血后背侧丘脑的细胞内pH比不完全缺血时更碱化。因此，在没有严重组织乳酸酸中毒的情况下，长时间缺血期间的残余脑血流量有助于皮质下区域缺血后脑能量代谢的恢复。完全缺血后这些区域恢复不佳的模式表明再灌注不足。总肌酸降低和严重的组织碱中毒可能是再灌注期间晚期组织损伤的生化标志物。
