丹酚酸A對大鼠腦缺血再灌注后細胞凋亡的保護作用及其機制

彭瀟，方世記，鄭麗云，邱偉文

（1.溫州醫科大學附屬第五醫院 神經內科，浙江 麗水 323000；2.溫州醫科大學附屬第五醫院 介入科，浙江 麗水 323000；3.溫州醫科大學附屬第六醫院 神經內科，浙江 麗水 323000）

丹酚酸A對大鼠腦缺血再灌注后細胞凋亡的保護作用及其機制

彭瀟1，方世記2，鄭麗云1，邱偉文3

（1.溫州醫科大學附屬第五醫院 神經內科，浙江 麗水 323000；2.溫州醫科大學附屬第五醫院 介入科，浙江 麗水 323000；3.溫州醫科大學附屬第六醫院 神經內科，浙江 麗水 323000）

目的：探討丹酚酸A（Sal A）對大鼠腦缺血再灌注后細胞凋亡的保護作用及其機制。方法：采用線拴法構建大腦中動脈缺血再灌注（MCA-IR）模型。將正常SD大鼠隨機分為假手術組（對照組）、MCA-IR模型組（MCA-IR組)、Sal A+MCA-IR組（Sal A組）；Sal A組于建模前1周每日腹腔注射1.0、2.5、5.0 mg/kg Sal A。于再灌注后24 h取梗死腦組織用TUNEL法檢測腦細胞凋亡，Western blot檢測磷酸化Akt（p-Akt）和Akt的表達，免疫組織化學法檢測海馬區胞漿型磷脂酶A2（cPLA2）的表達。結果：Sal A組海馬CA1區細胞凋亡率和MDA含量較MCA-IR組降低，而SOD量較MCA-IR組顯著增加（P＜0.05），MCA-IR組海馬區p-Akt表達較對照組顯著下降（P＜0.05），而cPLA2較對照組顯著增高（P＜0.05），1.0、2.5、5.0 mg/kg Sal A預處理后，MCA-IR模型大鼠海馬區cPLA2表達顯著降低（P＜0.05），而p-Akt表達顯著增加（P＜0.05）。結論：Sal A降低缺血再灌注損傷后細胞凋亡，起到損傷保護作用，其機制與其降低cPLA2表達，激活Akt信號通路有關。

丹酚酸A；細胞凋亡；蛋白激酶B；腦缺血再灌注；大鼠

Abstract: Objective:To investigate the protective effect of salvianolic acid A (Sal A) against apoptosis in cerebral ischemia-reperfusion model and its mechanism.Methods:SD rats were randomly divided into sham operation group (sham group), middle cerebral artery ischemia reperfusion model (MCA-IR) group (MCA-IR group), Sal A pretreatment and MCA-IR group (Sal A+MCA-IR group). MCA-IR was established in MCA-IR group and Sal A+MCA-IR group in which rats were pre-treated with 1.0, 2.5, 5.0 mg/kg Sal A via intraperitoneal injection daily for 1 week. The artery were reperfused for 24 h and rats were sacrificed. TUNEL was used to assayed the cell apoptosis, immunohistochemistry was implied to test the expression of cPLA2 and Western blot was undergone to analyzed p-Akt and total Akt. Immunohistochemistry was used to analyze the expression of cPLA2.Results:The apoptosis rate and MDA level in Sal A+MCA-IR group was lower, but SOD was higher than that in MCA-IR group (P＜0.05). The expression of p-Akt in Hippocampus of MCA-IR model decreased, while the expression of cPLA2 increased significantly compared with control group. 1.0, 2.5, 5.0 mg/kg Sal A pretreatment reversed the decrease of p-Akt and increase of cPLA2.Conclusion:Sal A inhibits the apoptosis through decreasing the expression of cPLA2 and activating Akt pathway signaling in MCA-IR model.

Key words:salvianolic acid A; apoptosis; protein kinase B; ischemia-reperfusion; rats

腦缺血再灌注引起的細胞凋亡和氧自由基的釋放是腦缺血嚴重臨床癥狀的主要原因[1-2]。研究證實胞漿型磷脂酶A2（cytosolic phospholipase A2，cPLA2）通過調節細胞內脂質分子的代謝，參與腦缺血再灌注誘導的細胞凋亡[3-4]。……