血管紧张素Ⅱ对人肝细胞白蛋白和胶原合成的影响

The effects of angiotensin Ⅱ on the synthesis of albumin and type Ⅰ collagen in human hepatic cells

目的 观察血管紧张素Ⅱ（AngⅡ）对人正常肝细胞白蛋白表达及Ⅰ型胶原合成的影响.方法 常规培养人正常肝细胞系HL-7702细胞并分为对照组、AngⅡ刺激组、AngⅡ十依贝沙坦组（共刺激组）.采用免疫荧光法和Western印迹法检测各组肝细胞中白蛋白及胶原改变;免疫荧光法观察各组肝细胞中是否有胶原合成;实时定量PCR法定量检测各组肝细胞中Ⅰ型胶原mR-NA表达水平的变化.结果 与对照组相比,经AngⅡ（10-7mol/L）处理72 h后,AngⅡ刺激组肝细胞中白蛋白表达减少（1.41±0.23比0.85±0.11,P=0.000）,Ⅰ型胶原mRNA的表达明显升高（1.00±0.08比3.72±0.19,P=0.000）,Ⅰ型胶原蛋白合成增加,而经依贝沙坦预处理后,共刺激组肝细胞白蛋白表达较AngⅡ刺激组明显增多（0.85±0.11比1.38±0.32,P=0.000）,肝细胞Ⅰ型胶原mRNA表达较AngⅡ刺激组显著下降（3.72±0.19比2.86±0.13,P=0.000）,Ⅰ型胶原蛋白合成减少.结论 AngⅡ经Ⅰ型受体诱导人肝细胞表达白蛋白减少,胶原合成增加.

Objective To investigate the effects of angiotensin Ⅱ （AngⅡ） on the expression of albumin and the synthesis of type Ⅰ collagen in human normal hepatic cells. Methods HL-7702 cells （human normal hepatocyte） were cultured and divided into control group, Ang Ⅱ treated group, an AngⅡ＋irbesartan （co-stimulated） group. The expressions of albumin and type Ⅰ collagen were detected by immunofluorescence and Western blotting, respectively. The mRNA level of type Ⅰ collagen was measured by real time-PCR（qRT-PCR）. Results After stimulated with 10-7 mol/L Ang Ⅱ for 72 hours, the expression of albumin significantly decreased in Ang Ⅱ treated group compared with control group （0.85±0.11 vs 1. 41±0.23,P=0.000）, while the mRNA expression increased in AngⅡ treated group compared with control group （1.00±0.08 vs 3.72±0.19,P=0.000）. In costimulated group, however, the expression of albumin significantly increased （0.85 ± 0.11 vs 1.38 ±0.32,P=0.000）,and mRNA expression （3. 72±0.19 vs 2.86±0.13,P=0.000） and synthesis of type Ⅰ collagen were reduced when compared with Ang Ⅱ treated group. Conclusions The reduction of albumin and elevated systhesis of type Ⅰ collagen in HL-7702 cells are induced via Ang Ⅱ AT1 receptor.