Effect of systemic temperature on hippocampal neuronal survival in transient global ischemia animal model

J Korean Neurol Assoc > Volume 15(1); 1997 > Article

Journal of the Korean Neurological Association 1997;15(1): 19-29.

일과성 전뇌 허혈 모델에서 체온이 해마의 신경보호에 미치는 영향

김용재, 나정호, 김범생

가톨릭대학교 의과대학 신경과학교실

Effect of systemic temperature on hippocampal neuronal survival in transient global ischemia animal model

Yong Jae Kim, M.D., Joung-Ho Rha, M.D., Beum Saeng Kim, M.D.

Deparment of Neurology, College of Medicine, Ewha Womans University Department of Neurology, College of Medicine, Catholic University

Abstract

It has been known that the hypothermia have protective effect on neuronal survival after ischemic damage. We performed this study to evaluate the effect of the small changes in postischemic body temperature on the histopathological change of hippocampus in the transient global cerebral ischemia model. Mongolian gerbils were subjected to this study. Nine animal subgroups were investigated, including naive gerbils who underwent sham operation or carotid artery occlusion with postischemic rectal temperature maintained at 32.5, 34.5, 36.5 and 38.5C respectively. Carotid occlusion was maintained for 10 minutes and then reperfusion started. During ischemia, body temperature was maintained 36.5℃ in all animals. For one hour after ischemia, body temperature was maintained constant at 36.5℃ in the normothermia group, 38.5℃ in the hyperthemia group, 34.5℃ in mild hypothermia group, and 32.5℃ in moderate hypothermia group respectively. Seven days after the operation, the surviving animals were decapitated and perfusion fixated. After preparing coronal brain slices, viable neurons in hippocampal region were counted using cresyl violet staining. There were significant differences in the hippocampal neuronal survival in normothermia and hyperthermia groups compared with shamoperated group(P<0,01), and neuronal damages in mild and moderate hyperthemia groups were not significantly different from sham operated. Survival rate at postischemic 7th day was also significantly lower in hyperthermia group. We could confirm the protective effect of hypothermia on ischemic neuronal damage by histopathological study. Also hyperthemia was observed to aggravate neuronal death, Careful control of body temperature might have clinical effect in ischemic stroke.