He Ping, Fan Yan-Ying, Zhang Lu-Yi, Hu Wei-Wei, Chen Zhong
College of Medicine, Zhejiang University, Hangzhou 310058, China.
Zhejiang Da Xue Xue Bao Yi Xue Ban. 2009 Nov;38(6):579-83. doi: 10.3785/j.issn.1008-9292.2009.06.005.
To investigate the effect of endogenous histamine on ischemic preconditioning induced cerebral ischemic tolerance in rats.
Wild-type (WT) mice and histidine decarboxylase knock-out (HDC-KO) mice were preconditioned by bilateral carotid artery occlusion (BCCAO) for 6, 10,or 14 min and reperfused for 48 h,then subjected to permanent BCCAO and the survival time of WT and HDC-KO mice subjected to permanent BCCAO was observed. Histamine levels in the hypothalamus, hippocampus, striatum and cortex at 0.5 h,5 h or 48 h after 10 min BCCAO were determined with high-performance liquid chromatography.
Ten minutes ischemic preconditioning significantly prolonged the survival time of WT mice subjected to permanent BCCAO. However,in HDC-KO mice, the ischemic tolerance was not induced with 10 min preconditioning. The histamine levels at 0.5 h or 48 h increased after 10 min preconditioning, but not at 5 h.
Endogenous histamine in brain may be an essential mediator in ischemic preconditioning induced cerebral ischemic tolerance.
探讨内源性组胺对大鼠缺血预处理诱导的脑缺血耐受性的影响。
野生型（WT）小鼠和组氨酸脱羧酶基因敲除（HDC-KO）小鼠通过双侧颈总动脉闭塞（BCCAO）分别预处理6、10或14分钟，再灌注48小时，然后进行永久性BCCAO，观察WT和HDC-KO小鼠永久性BCCAO后的存活时间。采用高效液相色谱法测定BCCAO 10分钟后0.5小时、5小时或48小时下丘脑、海马、纹状体和皮质中的组胺水平。
10分钟缺血预处理显著延长了接受永久性BCCAO的WT小鼠的存活时间。然而，在HDC-KO小鼠中，10分钟预处理未诱导出缺血耐受性。10分钟预处理后0.5小时或48小时组胺水平升高，但5小时时未升高。
脑内的内源性组胺可能是缺血预处理诱导脑缺血耐受性的重要介质。
