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目的:探索n 60Co γ射线诱导大鼠小肠上皮细胞(IEC-6)中CPT1A和CPT1B蛋白表达变化，并进一步研究肉碱棕榈酰转移酶1(CPT1)变化对受照细胞增殖的影响及相关分子机制。n 方法:IEC-6细胞经棕榈酸、血清饥饿以及血清饥饿联合棕榈酸处理后，给予0、5、10或15 Gy n 60Co γ射线照射，照射后24 h收集细胞并提取蛋白，利用Western blot方法检测CPT1A和CPT1B蛋白的表达水平变化；ETO是CPT1的小分子抑制剂，利用克隆形成率实验和CCK-8实验分析ETO抑制CPT1对n 60Co γ射线照射IEC-6细胞存活及增殖的影响；利用Western blot方法检测5 Gy n 60Co γ射线照射ETO处理IEC-6细胞48 h后细胞外信号调节激酶1/2(ERK1/2)、c-Jun氨基末端激酶(JNK)蛋白表达及磷酸化水平变化。n 结果:棕榈酸处理组中，CPT1A蛋白在15 Gy γ射线照射后表达量显著增加(n t＝-2.82，n P<0.05)。血清饥饿处理组中，CPT1A蛋白在5、10和15 Gy γ射线照射后表达量明显升高(n t＝-3.28、-8.72、-8.67，n P<0.05)；血清饥饿联合棕榈酸处理组中，CPT1A蛋白在5、10和15 Gy γ射线照射后表达量显著增加(n t＝-10.69、-7.02、-8.23, n P<0.05)，CPT1B蛋白在照射10和15 Gy γ射线照射后表达量显著增加(n t＝-3.73、-5.05, n P<0.05)。n 60Co γ射线照射后，ETO处理组细胞存活率及相对增殖率明显低于对照组(n t＝5.46、13.22，n P<0.05)；ERK1/2蛋白表达水平及JNK磷酸化水平明显低于对照组(n t＝4.01、3.29、10.68、14.44，n P<0.05)。n 结论:CPT1通过促进增殖通路中ERK1/2蛋白的表达和JNK的激活，从而使得n 60Co γ射线诱导IEC-6细胞损伤后的存活及增殖增加。n “,”Objective:To investigate the changes of CPT1A and CPT1B protein expression in rat intestinal epithelial cells (IEC-6) after n 60Co γ-ray irradiation, and the mechanism of the influence of carnitine palmitoyltransferase 1 (CPT1) on the proliferation of irradiated IEC-6 cells.n Methods:IEC-6 cells were cultured in serum-normal medium or in serum-starved medium overnight, and pretreated with 20 μmol/L palmitic acid (PA) before irradiation with 0, 5, 10, and 15 Gy. At 24 h after irradiation, the cellular protein was collected for the measurement of CPT1A and CPT1B proteins by Western blot. The influences of ETO, an inhibitor of CPT1, on the survival and proliferation of irradiated IEC-6 cells were analyzed by colony formation assay and CCK-8 assay. The protein expressions and phosphorylation levels of the extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) in 5 Gy irradiated IEC-6 cells pre-treated with ETO were analyzed by Western blot at 48 h after radiation.Results:When IEC-6 cells were cultured in serum-normal medium together with PA, the protein level of CPT1A was significantly increased after 15 Gy irradiation (n t=-2.82, n P<0.05). When IEC-6 cells were cultured in serum-starved medium, the protein level of CPT1A was significantly increased at 5, 10, and 15 Gy (n t=-3.28, -8.72, -8.67, n P<0.05). When IEC-6 cells were cultured in serum-starved medium together with PA, the protein levels of CPT1A were significantly increased at 5, 10 and 15 Gy (n t=-10.69, -7.02, -8.23, n P<0.05), the protein levels of CPT1B were significantly increased at 10 and 15 Gy (n t=-3.73, -5.05, n P<0.05). After irradiation, the survival and proliferation of IEC-6 cells in ETO group were significantly lower than those in control group (n t=5.46, 13.22, n P<0.05), and the protein level of ERK1/2 and p-JNK in ETO group were significantly lower than those in control group (n t=4.01, 3.29, 10.68, 14.44, n P<0.05).n Conclusions:CPT1 promoted radiation-induced IEC-6 injury cells survival and proliferation by enhancing the expression level of ERK1/2 protein and the activity of JNK.