尾加压素Ⅱ对培养的心脏成纤维细胞增殖和胶原基因表达的影响

Effects of urotensinⅡ on cultured cardiac fibroblast proliferation and collagen typeⅠmRNA expression

目的观察尾加压素Ⅱ(urotensinⅡ,UⅡ)在体外对乳鼠心脏成纤维细胞(CFs)增殖和Ⅰ型胶原(CoL-Ⅰ)基因表达的直接影响,以探讨UⅡ在心力衰竭心肌重塑中的作用。方法以胰酶消化和差速贴壁法分离和纯化SD乳鼠的CFs,采用四氮唑盐(MTT)比色法测定细胞增殖,RT-PCR测定CoL-ⅠmRNA表达水平。结果UⅡ对CFs增殖呈浓度依赖性,随着UⅡ作用浓度的增加,MTT光吸收值呈先升高后降低的趋势,其中1×10-8 mol/L和1×10-9 mol/L的UⅡ作用显著(P<0.05);1×10-7 mol/L、1×10-8 mol/L和1×10-9 mol/L浓度的UⅡ能促进CFs的CoL-ⅠmRNA表达(P<0.01)。结论UⅡ可直接促进CFs的增殖及CoL-ⅠmRNA表达,作用大小与UⅡ浓度有关,提示UⅡ在心力衰竭心肌重塑的病理生理过程中可能发挥重要作用。

Objective To observe the effect of urotensinⅡon cultured cardiac fibroblast collagen typeⅠmRNA expression and proliferation, thereby to explore the role of urotensinⅡin myocardial remodeling in the event of cardiac failure. Methods Cardiac fibroblasts of neonatal Sprague-Dawley rats isolated by trypsin digestion method were stimulated by urotensinⅡ at varied concentrations when the cells reached growth arrest. MTT assay was employed to measure the proliferation and determine the number of the cells, and reverse transcriptional (RT)-PCR used to detect the collagen mRNA expression. Results With the increase of urotenisnⅡconcentration, the optical density at 570 nm of the fibroblasts as shown by MTT assay first increased but then decreased, and remained at a significantly higher level in the cells treated with 1×10-8 or 1×10-9 mol/L urotensinⅡas compared with the control (P<0.05). The collagen type ⅠmRNA levels of the cells treated with 1×10-7, 1×10-8 or 1×10-9mol/L urotensinⅡ were significantly higher than that of the control cells (P<0.01). Conclusion UrotensinⅡcan directly induce cardiac fibroblast proliferation and significantly increase collagen typeⅠmRNA expression, suggesting the crucial role of urotensin Ⅱ in myocardial remodeling.