Zhou Zhu-Ying, Li Guang-Qian
Department of Neurology, Yuying Children's Hospital Affiliated to Wenzhou Medical College, Wenzhou, Zhejiang 325027, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2011 Jan;13(1):44-9.
To investigate the effects of the calmodulin inhibitor W-7 on the expression of the key marker of ERS GRP78 and neuronal apoptosis in the immature rat hippocampus after status convulsion (SC).
One hundred and seventeen male Sprague-Dawley rats aged 19-21 days were randomly divided into three groups: normal saline control (control), SC with and without W-7 pretreatment. Each of the 3 groups was further subdivided into subgroups sacrificed at 4, 24 and 48 hrs. SC model was prepared using lithium-pilocarpine. GRP78 mRNA expression in the hippocampus was detected by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). GRP78 protein was ascertained by immunohistochemistry. Neuronal apoptosis was observed with TdT-mediated dUTP nick end labeling (TUNEL).
The expression of GRP78 mRNA was significantly increased in the non-pretreated SC group compared with the control group 24 hrs after injection of saline or lithium-pilocarpine (P<0.01), and the expression of GRP78 protein also increased markedly in the seizure group compared with the control group 24 and 48 hrs after the injection (P<0.01). The expression of GRP78 mRNA and protein in the W-7 pretreatment group was significantly higher than both the control and the non-pretreated seizure groups 24 and 48 hrs after injection. The TUNEL positive cells in the hippocampus CA1 in the non-pretreated SC group 24 and 48 hrs after injection (21.0 ± 2.5 and 29.4 ± 2.8, respectively) were increased compared to the control group (7.1 ± 1.4 and 7.3 ± 1.6, respectively; P<0.01). W-7 pretreatment decreased TUNEL positive cells to 15.0 ± 2.5 and 20.0 ± 2.9 at 24 and 48 hrs after injection compared to the non-pretreated seizure group (P<0.01), but the number of TUNEL positive cells in the W-7 pretreatment group remained significantly greater than in the control group (P<0.01).
W-7 may up-regulate the expression of GRP78 and reduce the number of apoptotic neurons, thus provides a neuroprotective effect against brain damage following SC.
探讨钙调蛋白抑制剂W-7对惊厥持续状态（SC）后未成熟大鼠海马中内质网应激关键标志物葡萄糖调节蛋白78（GRP78）表达及神经元凋亡的影响。
将117只19-21日龄的雄性Sprague-Dawley大鼠随机分为三组：生理盐水对照组（对照组）、SC组以及W-7预处理的SC组。每组再进一步细分为在4、24和48小时处死的亚组。采用锂-匹罗卡品制备SC模型。通过半定量逆转录-聚合酶链反应（RT-PCR）检测海马中GRP78 mRNA的表达。通过免疫组织化学确定GRP78蛋白。采用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法（TUNEL）观察神经元凋亡情况。
与注射生理盐水或锂-匹罗卡品24小时后的对照组相比，未预处理的SC组中GRP78 mRNA的表达显著增加（P<0.01），并且与注射后24和48小时的对照组相比，癫痫发作组中GRP78蛋白的表达也显著增加（P<0.01）。注射后24和48小时，W-7预处理组中GRP78 mRNA和蛋白的表达显著高于对照组和未预处理的癫痫发作组。与对照组（分别为7.1±1.4和7.3±1.6）相比，注射后24和48小时未预处理的SC组海马CA1区的TUNEL阳性细胞增加（分别为21.0±2.5和29.4±2.8；P<0.01）。与未预处理的癫痫发作组相比，W-7预处理使注射后24和48小时的TUNEL阳性细胞减少至15.0±2.5和20.0±2.9（P<0.01），但W-7预处理组中TUNEL阳性细胞的数量仍显著多于对照组（P<0.01）。
W-7可能上调GRP78的表达并减少凋亡神经元的数量，从而对SC后脑损伤提供神经保护作用。
