肾脏集合管的上皮钠离子通道（ENaC）激活是引起肾病综合征（NS）水肿的新机制，该通道的表达量和开放率受AMPK-泛素-PIP2/clathrin通路调控。黄芪汤是治疗糖尿病肾病的良方，我们临床观察发现其也可改善NS水肿，但具体效应和机制仍待明确。我们预初研究显示黄芪汤可激活AMPK和抑制ENaC，据此我们推测黄芪汤可通过激活AMPK-泛素-PIP2/clathrin通路以抑制ENaC，从而改善NS水肿。基于该假设，本项目拟通过大鼠腹腔注射PAN和纤溶酶刺激集合管上皮细胞的方式分别构建NS水肿的动物和细胞模型，利用基因敲除、siRNA干扰、药物阻断等方法干预AMPK-泛素-PIP2/clathrin通路，并运用细胞电生理、细胞生物学、分子生物学、组织学等技术，研究黄芪汤干预ENaC以改善NS水肿的作用以及上述通路在其中的调控效应，阐明黄芪汤利水作用的药理机制，为其临床应用提供理论和实验基础。

The activation of epithelial sodium channel (ENaC) in renal collecting duct is a novel mechanism of edema formation in nephrotic syndrome (NS), in which AMPK-ubiquitin-PIP2/clathrin pathway plays an important role by affecting both the expression and open probability of ENaC. Traditional Chinese Medicine compound Huangqi decoction is effective on diabetic nephropathy. Our clinical observation has also shown that Huangqi decoction can ameliorate edema formation in NS, while its exact effect and underlying mechanism remains to be identify. Our previous research showed that Huangqi decoction can activate AMPK as well as inhibit ENaC, from which it is hypothesized that Huangqi decoction can inhibit ENaC through the activation of AMPK-ubiquitin-PIP2/clathrin pathway, thus ameliorating edema formation in NS. In the current study, we plan to establish the animal and cell model of edema formation in NS by intraperitoneal injection of PAN to male Sprague-Dawley rat and plasmin stimulation to collecting duct epithelial cell, respectively. Afterwards, experimental intervention (gene knockout, siRNA suppression, and specific inhibitor) will be applied to regulate the activity of AMPK-ubiquitin-PIP2/clathrin pathway, and researching techniques of cellular electrophysiology, cellular biology, molecular biology and histology will be used, aiming to investigate the effect of Huangqi decoction on ameliorating edema formation in NS by modulating ENaC, and the regulatory role of AMPK-ubiquitin-PIP2/clathrin pathway in this process. The current study will thus identify the pharmacological mechanism of Huangqi decoction’s anti-edema effect, and provide theoretical and experimental basis for its clinical application.