TNF-α诱导Gq-Ca^(2+)信号途径在鼠肺成纤维细胞增殖中的作用

Role of TNF-α induced Gq-Ca^(2+) signal pathway in proliferation of lung fibroblast of rat

目的研究TNF-α诱导Gq-Ca2+信号途径对鼠肺成纤维细胞增殖的机制及尼莫地平(Nim)的拮抗效应。方法以不同浓度的TNF-α刺激4—5代SD大鼠乳鼠肺成纤维细胞,氯氨T法检测成纤维细胞羟脯氨酸的含量;Western blot检测成纤维细胞Gq蛋白的表达,流式细胞技术检测细胞内Ca2+的含量;酶联免疫吸附试验检测各组成纤维细胞内环磷酸腺苷(cAMP)的水平。结果 Gq蛋白的结果显示随TNF-α剂量的增加而增加;Ca2+和羟脯氨酸的结果显示在10 ng/ml TNF-α剂量组有明显增加,与各组比较有明显的统计学意义(P<0.05);当TNF-α联合Nim后,促使cAMP表达量增强,同时使羟脯氨酸的表达降低。结论 TNF-α介导Gq-Ca2+信号途径使羟脯氨酸表达增强,Nim通过提高cAMP的水平来拮抗TNF-α介导的效应。

Objective To explore the role of tumor necrosis factor-alpha（TNF-α）induced Gq-Ca2＋ signal pathway in lung fibroblast proliferation of rat,and the antagonistic effect of nimodipine（Nim）.Methods Cultured lung fibroblasts from SD neonatal rat were stimulated by different concentrations of TNF-α,then determined the level of hydroxyproline in fibroblast by chloramine T method,examined the expression of Gq protein in fibroblast by Western blot,detected the concentration of intracellular free Ca2＋ by FCM,and measured the level of cAMP in fibroblast by ELISA.Results The results showed that Gq protein expression was increased with the increase of TNF-α dose;the levels of Ca2＋ and hydroxyproline were significantly increased in 10 ng/ml TNF-α group,there was significant difference compared with other groups（P0.05）;while the combined use of TNF-α with Nim might raise the expression of cAMP and reduce the expression of hydroxyproline.Conclusion It was suggested that TNF-α induced Gq-Ca2＋ signal pathway raising the expression of hydroxyproline,and Nim antagonized TNF-α mediated effects through raising the level of cAMP.