Vilas-Boas Walkíria Wingester, Ribeiro-Oliveira Antônio, Pereira Regina Maria, Ribeiro Renata da Cunha, Almeida Jerusa, Nadu Ana Paula, Simões e Silva Ana Cristina, dos Santos Robson Augusto Souza
Department of Physiology, Laboratory of Hypertension, Biological Sciences institute, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
World J Gastroenterol. 2009 May 28;15(20):2512-9. doi: 10.3748/wjg.15.2512.
To measure circulating angiotensins at different stages of human cirrhosis and to further evaluate a possible relationship between renin angiotensin system (RAS) components and hemodynamic changes.
Patients were allocated into 4 groups: mild-to-moderate liver disease (MLD), advanced liver disease (ALD), patients undergoing liver transplantation, and healthy controls. Blood was collected to determine plasma renin activity (PRA), angiotensin (Ang) I, Ang II, and Ang-(1-7) levels using radioimmunoassays. During liver transplantation, hemodynamic parameters were determined and blood was simultaneously obtained from the portal vein and radial artery in order to measure RAS components.
PRA and angiotensins were elevated in ALD when compared to MLD and controls (P < 0.05). In contrast, Ang II was significantly reduced in MLD. Ang-(1-7)/Ang II ratios were increased in MLD when compared to controls and ALD. During transplantation, Ang II levels were lower and Ang-(1-7)/Ang II ratios were higher in the splanchnic circulation than in the peripheral circulation (0.52 +/- 0.08 vs 0.38 +/- 0.04, P < 0.02), whereas the peripheral circulating Ang II/Ang I ratio was elevated in comparison to splanchnic levels (0.18 +/- 0.02 vs 0.13 +/- 0.02, P < 0.04). Ang-(1-7)/Ang II ratios positively correlated with cardiac output (r = 0.66) and negatively correlated with systemic vascular resistance (r = -0.70).
Our findings suggest that the relationship between Ang-(1-7) and Ang II may play a role in the hemodynamic changes of human cirrhosis.
测定人类肝硬化不同阶段循环血管紧张素水平，并进一步评估肾素血管紧张素系统（RAS）各组分与血流动力学变化之间的可能关系。
将患者分为4组：轻度至中度肝病（MLD）组、晚期肝病（ALD）组、肝移植患者组和健康对照组。采集血液，采用放射免疫分析法测定血浆肾素活性（PRA）、血管紧张素（Ang）I、Ang II和Ang-(1-7)水平。在肝移植过程中，测定血流动力学参数，并同时从门静脉和桡动脉采集血液以测量RAS各组分。
与MLD组和对照组相比，ALD组的PRA和血管紧张素水平升高（P < 0.05）。相反，MLD组的Ang II显著降低。与对照组和ALD组相比，MLD组的Ang-(1-7)/Ang II比值升高。在移植过程中，内脏循环中的Ang II水平低于外周循环，而Ang-(1-7)/Ang II比值高于外周循环（0.52±0.08对0.38±0.04，P < 0.02），而外周循环中的Ang II/Ang I比值与内脏水平相比升高（0.18±0.02对0.13±0.02，P < 0.04）。Ang-(1-7)/Ang II比值与心输出量呈正相关（r = 0.66），与全身血管阻力呈负相关（r = -0.70）。
我们的研究结果表明，Ang-(1-7)与Ang II之间的关系可能在人类肝硬化的血流动力学变化中起作用。
