摘要
目的探讨血管紧张素-Ⅱ(Ang-Ⅱ)对大鼠胚心成纤维细胞(FB)的促增殖作用和促胶原蛋白合成作用及其机制。方法应用同位素掺入技术,检测Ang-Ⅱ对体外大鼠胚心FB的促增殖和促胶原蛋白合成作用,并应用放射自显影和荧光法,检测FB上的Ang-Ⅱ受体分布和细胞内游离Ca2+浓度。结果Ang-Ⅱ使FB[3H]TdR和[3H]脯氨酸的掺入率明显增加,放射自显影显示在细胞表面有大量银颗粒出现,图像分析显示膜上受体银颗粒在竞争抑制组明显少。细胞内游离Ca2+浓度较高。结论Ang-Ⅱ有刺激大鼠胚心FB增殖和胶原蛋白合成作用,大鼠心肌FB膜上有Ang-Ⅱ受体,受体磷酸化后,通过细胞内游离Ca2+浓度增加等一系列细胞内信号系统的活化,出现FB的增殖和胶原蛋白合成。
AIM: To investigate the effects of angiotensin-Ⅱ (Ang-Ⅱ) on the proliferation and collagen synthesis in rat cardiac fibroblasts and the expression of Ang-Ⅱ receptor on fibroblasts. METHODS: [3H]-TdR and [3H]-prolin at different concentrations were incubated with the confluent fibroblasts of newborn rats stimulated by Ang-Ⅱ. Receptor of Ang-Ⅱ on fibroblasts and intracellular free calcium ions were examined by autoradiograms and fluorescence technique. RESULTS: In the presence of Ang-Ⅱstimulation, the increase in incorporation of [3H]-TdR and [3H]-prolin was much higher than that of control in a dose-dependent manner. Autoradiograms showed that Ang-Ⅱ was uniformly distributed over the membrane of the fibroblasts. The silver grains on fibroblasts were obviously decreased after adding unlabeled Ang-Ⅱ by the autoradiograms. The concentration of free calcium ions was increased in fibroblast. CONCLUSION: These findings suggest that Ang-Ⅱ promotes fibroblast proliferation and the syntheses of collagen protein, in which Ang-Ⅱ binds to the membrane receptor of fibroblasts to activate the signal system in cells, such as intracellular free calcium ions. [
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2005年第1期89-91,共3页
Chinese Journal of Pathophysiology
