蛋白激酶B(Akt)在沙土鼠海马缺血耐受中的表达

目的：探讨沙土鼠海马缺血耐受与CAl区蛋白激酶B(Akt)表达及锥体神经元凋亡之间的关系。方法：沙土鼠16只随机分为A(2min缺血组)、B(5min缺血组)、C：(2min缺血 5min缺血组)、D(假手术组)4组，每组4只。免疫组化(SP法)检测海马CAl区Akt表达，末端转移酶介导的缺口末端标记(TUNEL)法检测锥体细胞凋亡。结果：A、C两组表达的Akt阳性细胞数明显多于B组，D组无明显从Akt表达;B组锥体细胞凋亡较A、C两组显著，D组未见明显凋亡细胞。结论：Akt可能通过抑制锥体细胞的凋亡参与介导沙土鼠海马缺血耐受。

Expression of Akt/Protein Kinase B in Hippocampal Ischemic Tolerance in Gerbils

Objective: To investigate the expression of protein kinase B(Akt) and the apoptosis of pyramidal neurons in hippocampal CAl region and their relationships with hippocampal ischemic tolerance in gerbils. Methods: Sixteen gerbils were randomly divided into 4 groups( n = 4 for each group): group A(2 minutes of ischemia), group 8(5 minutes of ischemia), group C(first subjected to 2 minutes of ischemia, then 5 minutes of ischemia 2 days later), and group D(sham-operated). The expression of Akt and the apoptosis of pyramidal neurons in hippocampal CAl region were examined by immunohistochemistric staining and terminal deoxynucleotidyl trans-ferase-mediated dUTP-biotin nick end labeling(TUNEL) respectively. Results: More Akt-positive neurons were detected in both group A and group C as compared with those in group 8 in CAl region. However, increased apoptotic neurons were observed in group B as compared with those in group A and group C. Croup D showed no significant Akt-positive neurons and apoptotic pyramidal cells. Conclusion: Akt may mediate hippocampal ischemic tolerance by inhibiting the apoptosis of pyramidal neurons in CAl region in gerbils.