目的:研究咖啡因对LY294002 诱导的小脑颗粒神经元凋亡的保护作用。方法:DNA 断裂分析采用琼脂糖凝胶电泳法,[Ca2+]i 测定采用Fura2 荧光技术,磷酸化cJun 分析采用免疫荧光法,cJun 含量和JNK 活性分析采用Western blot 法。结果:咖啡因对LY294002 诱导小脑颗粒神经元凋亡具浓度依赖性的保护作用,这种保护作用不依赖[Ca2+]i 的升高或cAMP的生物效应。咖啡因可抑制cJun 氨基末端激酶(JNK) 的活性,降低细胞内磷酸化cJun 的含量和cJun 的表达。结论:咖啡因可抑制JNK 活性,阻断cJun 磷酸化及其介导的细胞凋亡信号转导系统,从而对LY294002 诱导小脑颗粒神经元凋亡具有保护作用 Objective: To study the protective effects of caffeine on apoptosis of cerebellar granule neurons induced by LY294002. Methods: DNA fragmentation analysis was performed by agarose gel electrophoresis, [Ca2 +] i determination by Fura-2 fluorescence technique, phosphorylation c-Jun analysis by immunofluorescence, c-Jun content and JNK activity by Western blot. RESULTS: Caffeine had a concentration-dependent protective effect on cerebellar granule neurons induced by LY294002. This protective effect did not depend on the increase of [Ca2 +] i or the biological effect of cAMP. Caffeine can inhibit c-Jun amino-terminal kinase (JNK) activity, reduce the content of intracellular phosphorylated c Jun and c Jun expression. CONCLUSION: Caffeine can inhibit the activity of JNK and block the phosphorylation of c-Jun and its signal transduction system of apoptosis, so it can protect LY294002-induced apoptosis of cerebellar granule neurons