关键词: 亚低温; 脑缺血; 再灌注; 脑水肿

Abstract: Objective To study the therapeutic effects of mild hypothermia on the cerebral edema at differentreperfusion time window after transient ischemia in rats.Methods Ninety-six male Sprague Dawley rats were randomly divided into mild hypothermiagroup and normothermia group. Middle cerebral artery occlusion and reperfusion (MCAO/R)were achieved with the use of an intraluminal filament to occlude the left MCA for 3, 6 or 9 hours.Sham-operations were also done. Mild hypothermia (32℃～35℃) was given for 3 or 5 hours.At the 24th hour after reperfusion, all rats were decapitated. Brain water content (BWC) wasdetermined by dry-wet method.Results Compared with sham-operated group, the BWC of all MCAO/R groups were increasedsignificantly. The BWCs in mild hypothermia for 3 hours group and 5 hours group afterMCAO3 h/R were 79.39% ± 2.44% and 79.20% ± 1.55%, while the BWC in normothermia groupafter MCAO3 h/R was 82.16% ± 1.50% (P <0.05). There were no significant differences betweenhypothermia group and normothermia group in MCAO6 h/R and MCAO9 h/R groups.Conclusion Mild hypothermia significantly reduces brain edema when reperfusion is performedearly after MCAO. However, mild hypothermia has no significant effect on brain edema whenreperfusion is prolonged.

Key words: Hypothermia; Brain ischemia; Reperfusion Brain edema