【摘要】 目的:观察重组Leptin干预对原代培养的新生大鼠下丘脑神经元STAT3磷酸化蛋白的表达的影响,探讨Leptin干预及STAT3的磷酸化在肥胖发生中的可能作用,以期更加深入的研究肥胖症发生的中枢信号转导机制。方法:取新生5～7天SD大鼠下丘脑神经元,分散培养,观察下丘脑神经元的形态和NSE免疫染色鉴定活性;培养7天后,Leptin(100ng/ml培养液)干预24h,免疫细胞化学染色检测下丘脑神经元STAT3和磷酸化STAT3蛋白的表达情况。结果:新生大鼠下丘脑培养神经细胞接种时为圆形,逐渐贴壁、伸出突起;培养7～10天,神经细胞生长良好,细胞胞体逐渐增大,胞核和核仁清晰可见。神经元多数为突起多极细胞。神经细胞NSE染色呈阳性,胞浆和突起被染成棕色;而非神经细胞呈阴性反应。无Leptin干预时,下丘脑神经元胞浆和胞核内STAT3蛋白表达呈阳性,而磷酸化STAT3蛋白呈阴性表达。Leptin干预24h后,培养下丘脑神经元的胞核和胞浆内均有磷酸化STAT3蛋白的表达,呈棕黄色。STAT3蛋白表达仍为阳性。结论:重组Leptin干预可以影响培养的下丘脑神经元中STAT3磷酸化蛋白的表达,并增强其活性。更多还原

【Abstract】 Objective: To observe the expression of STAT3 protein and its phosphorylation by Leptin administration in the cultured hypothalamic cells of newly born SD rats in vitro and elucidate the cellular mechanism of the tyrosine phosphorylation of STAT3 protein in obesity. Methods: The hypothalamic cells were isolated from the newly born SD rats, and cultured with DMEM for 6 days. Then the confluent cells, which had been cultured with serum free DMEM for 24 h, were stimulated by 100ng/ml Leptin for 24 h. The abundance of NSE and the phosphorylation of STAT3 protein was assayed by immunocytochemistry with anti-NSE antibody and anti-phosphor-tyrosine (705) STAT3 antibody. Results: The neurons in neuronal dissociated culture from newly born SD rat hypothalamus in vitro were investigated. During the day 7￣10, the cultured hypothalamic cells grew well and fast, and the cells expressed NSE, but the non-neuron cells were negative. In control group, the expression of STAT3 protein in cultured hypothalamic cell was positive, but phospho-STAT3 protein expression was negative. After Leptin administration for 24 h, the expression of phospho-STAT3 protein was found. Conclusion: For the first time, STAT3 protein phosphorylation were found by the cultured hypothalamic cells with Leptin administration in vitro.更多还原