Phosphorylation of extracellular signal-regulated kinase and p27(KIPl) after retinal detachment.

目得：细胞外信号调节激酶（ERK）通路在视网膜脱离后细胞周期蛋白D1和p27（KIP 1）的表达、p27（KIP 1）的磷酸化和增殖活性中的作用被检测。方法：应用免疫组织化学方法检测C57 B16小鼠正常眼和视网膜脱离后15 min、2 d和4 d眼的磷酸化ERK 1/2、细胞周期蛋白D1、p27（KIP 1）、丝氨酸10位磷酸化的p27（KIP 1（S10-磷酸-p27）和抗增殖细胞核抗原（PCNA）抗体，用或不用特异性ERK抑制剂PD 98059处理。分离小鼠Muller细胞，并使用Western印迹法检测暴露于碱性成纤维细胞生长因子（bFGF）后，有和没有PD 98059处理的p27（KIP 1）和细胞周期蛋白D1的变化。研究结果：在正常视网膜中，在内核层（INL）的中间亚层中观察到p27（KIP 1）的核免疫反应，而不是S 10-磷酸化-p27或pERK 1/2， 关于我们 穆勒神经胶质细胞的位置在视网膜脱离后15 min，在INL中观察到p27（KIP 1）、S10-磷酸化-p27和pERK 1/2阳性核，而PD 98095处理后未观察到pERK 1/2或S10-磷酸化-p27的免疫反应性。视网膜脱离后第2天，INL中细胞周期蛋白D1被诱导，PD 98059抑制该诱导。脱膜后4天，p27（KIP 1）免疫反应阴性，cyclin D1和PCNA表达。在PD 98059处理的小鼠中，p27（KIP 1）的消失被抑制，而细胞周期蛋白D1和PCNA的表达未观察到。与对照组相比，bFGF处理组小鼠Muller细胞中p27（KIP 1）的表达水平相对降低，cyclin D1的表达水平相对升高。PD 98059处理抑制了细胞周期蛋白D1的诱导和p27（KIP 1）的降低。结论：ERK磷酸化、p27（KIP 1）和cyclin D1表达参与视网膜脱离后Muller细胞增殖少

PURPOSE: The roles of the extracellular signal-regulated kinase (ERK) pathway in the expression of cyclin D1 and p27(KIP1), the phosphorylation of p27(KIP1), and proliferation activity were examined after retinal detachment. METHODS: Normal eyes and eyes at 15 min, 2 and 4 days after retinal detachment in C57B16 mice were examined by immunohistochemistry using anti-phosphorylated (p) ERK1/2, anti-cyclin D1, anti-p27(KIP1), anti-p27(KIP1) phosphorylated at serine 10 (S10-phospho-p27), and anti-proliferating cell nuclear antigen (PCNA) antibodies with or without treatment with a specific ERK inhibitor, PD98059.. Mouse Muller cells were isolated and examined for alteration of p27(KIP1) and cyclin D1 after exposure of basic fibroblast growth factor (bFGF) with and without treatment of PD98059 using Western blotting. RESULTS: In the normal retina, nuclear immunoreactivity for p27(KIP1), but not S10-phospho-p27 or pERK1/2, was observed in the middle sublayer of the inner nuclear layer (INL), … More where Muller glial cells are situated. At 15 min after the retinal detachment, p27(KIP1), S10-phospho-p27 and pERK1/2-positive nuclei were noted in the INL, whereas immunoreactivity for pERK1/2 or S10-phospho-p27 was not observed after treatment with PD98095. Cyclin D1 was induced in the INL 2 days after the retinal detachment, and the induction was inhibited by PD98059. At 4 days after the detachment, p27(KIP1) immunoreactivity was not observed, and cyclin D1 and PCNA were expressed. The disappearance of p27(KIP1) was suppressed, whereas expression of cyclin D1 and PCNA was not observed in mice treated with PD98059. Exposure of bFGF relatively decreased the expression level of p27(KIP1) and increased the level of cyclin D1 in mouse Muller cells, compared with control level. Induction of cyclin D1 and decrease in p27(KIP1) were inhibited with treatment of PD98059. CONCLUSION: Phosphorylation of ERK and expression of p27(KIP1) and cyclin D1 are involved in the proliferation of Muller cells after retinal detachment. Less