银杏内酯对拟老年痴呆模型大鼠学习记忆能力的影响

Effect of Ginkgolides on capabilities of learning and memory in Alzheimer's disease-like rat

目的:探讨银杏内酯对拟老年痴呆大鼠学习记忆能力影响的可能机制。方法:大鼠海马微量注射冈田酸(OA),银杏内酯灌胃。水迷宫实验检测大鼠学习记忆能力;银染观察大鼠脑内神经原纤维缠结(NFT);免疫组化观察大鼠脑内bax、bcl-2的表达。结果:与对照组比较,模型组大鼠学习记忆能力下降,NFT表达增多明显,bcl-2免疫阳性神经元减少明显,bax免疫阳性神经元增多明显;与模型组相比,银杏内酯组大鼠学习记忆能力明显提高,NFT表达减少明显,bcl-2免疫阳性神经元增多明显,bax免疫阳性神经元减少明显。结论:银杏内酯提高拟老年痴呆大鼠的学习记忆能力可能与其抑制OA对tau蛋白的磷酸化,减少神经细胞的凋亡,从而对神经元产生保护作用有关。

Objective： To investigate the mechnism through which Ginkgolides affect the learning and memory abilities in Alzheimer＇s disease-like rats. Methods： Okadaic acid （OA） was injected into the rat hippocampus and Ginkgolides solution was gavaged to experimental group for consecutive 4 weeks. Learning and memory test were used through Morris water maze assembles, The neurofibrillary tangles （NFT） in the hippocampus were observed by Bielschowsky stain and expressions of bax and bcl 2 were detected by immunohistochemistry. Results： Compared with the control rats, the learning and memory abilities in the model rats were weakened significantly in experimental group, NFTs were observed in the hippocampal CA1 region. The expression of bax positive neurons in the CA1 region increased and that of bcl-2 positive neurons decreased greatly. While in comparison with the model rats, the learning and memory abilities in the Ginkgolides-gavaqed rats were increased significantly. NFTs reduced in hippocampal CA1 region. The expressions of bax positive neurons in the CA1 region decreased and the expressions of bcl-2 positive neurons increased greatly in the rats gavaged with Ginkgolides. Conclusion： Ginkgolides can inhibit the function of OA and protect the nerve cells of Alzheimer＇s disease-like rats,so it could have the protective effect on learning and memory abilities.