Xu Z, Xu B, Xu C
Department of Urology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Ganhe Road 110, Shanghai, 200437, China.
Ir J Med Sci. 2015 Jun;184(2):297-304. doi: 10.1007/s11845-014-1103-6. Epub 2014 Mar 25.
Urinary angiotensinogen (AGT) mainly derives from the AGT produced in proximal tubular cells. Evidence exists that supports the correlation between urinary AGT and circulating AGT.
To investigate the role of urinary AGT as a potential biomarker of intrarenal renin-angiotensin system activity in Chinese chronic kidney disease (CKD) patients.
ELISA-based method used to quantify urinary AGT. Analyzed the relationship between urinary AGT and intrarenal angiotensin II (Ang II) activity in 128 CKD patients. ELISA was applied to measure the urinary and plasma renin activity, AGT, Ang II and aldosterone. Furthermore expression levels of intrarenal renin, AGT, Ang II and Ang II receptor were examined by immunohistochemistry staining (IHCS) in 72 CKD patients undergoing renal biopsy.
The logarithmic transformation Log(urinary AGT/UCre) levels showed a normal distribution. Therefore, Log(urinary AGT/UCre) levels were used for the analyses. Average urinary AGT was 2.02 ± 0.55 ng/(mg Cr). Hypertension, urinary protein, urinary Ang II and urinary type IV collagen (Col IV) positively correlated with urinary AGT. Estimated glomerular filtration rate (eGFR), urinary sodium and serum AGT negatively correlated with urinary AGT. Multiple regression analysis indicated that low serum AGT, high urinary protein, urinary Ang II and urinary Col IV correlated significantly with high urinary AGT.
We observed positive correlation between urinary AGT and positive IHCS area of AGT, Ang II and Ang II type 1 receptor in renal tissue. These data suggest that urinary AGT might be a potential biomarker of intrarenal Ang II activity in CKD patients.
尿血管紧张素原（AGT）主要来源于近端肾小管细胞产生的AGT。有证据支持尿AGT与循环AGT之间的相关性。
探讨尿AGT作为中国慢性肾脏病（CKD）患者肾内肾素-血管紧张素系统活性潜在生物标志物的作用。
采用基于酶联免疫吸附测定（ELISA）的方法定量尿AGT。分析128例CKD患者尿AGT与肾内血管紧张素II（Ang II）活性之间的关系。应用ELISA法检测尿和血浆肾素活性、AGT、Ang II和醛固酮。此外，对72例接受肾活检的CKD患者进行免疫组织化学染色（IHCS）检测肾内肾素、AGT、Ang II和Ang II受体的表达水平。
对数转换后的Log(尿AGT/尿肌酐)水平呈正态分布。因此，采用Log(尿AGT/尿肌酐)水平进行分析。尿AGT平均水平为2.02±0.55 ng/(mg Cr)。高血压、尿蛋白、尿Ang II和尿IV型胶原（Col IV）与尿AGT呈正相关。估计肾小球滤过率（eGFR）、尿钠和血清AGT与尿AGT呈负相关。多元回归分析表明，低血清AGT、高尿蛋白、尿Ang II和尿Col IV与高尿AGT显著相关。
我们观察到尿AGT与肾组织中AGT、Ang II和1型Ang II受体的免疫组织化学阳性染色面积呈正相关。这些数据表明，尿AGT可能是CKD患者肾内Ang II活性的潜在生物标志物。
