胎盘血管功能失稳态是子痫前期的核心病变，但机理不清。本课题组前期原创性发现，血管紧张素Ⅱ-1型受体（AT1R）自身抗体（AT1-AA）阳性的子痫前期患者胎盘血管平滑肌上介导舒张的大电导钙激活钾通道（BKCa）和电压依赖钾通道（KV）表达下降。本项目拟通过构建BKCa/KV通道敲除大鼠，利用膜片钳、单细胞张力检测等技术，明确AT1-AA通过持久激活AT1R-PLC-PKC信号通路抑制胎盘血管平滑肌BKCa/KV，进而引起血管张力升高的作用；采用放射配体结合实验、荧光共振能量转移等技术，从AT1R磷酸化障碍、内吞囊泡形成及转运蛋白改变、受体构象和合成速率异常、细胞膜流动性下降等角度， 寻找AT1-AA致胎盘血管平滑肌AT1R及下游信号持久激活的关键分子机制。本课题围绕“探讨血管稳态与重构的调控机制”的总目标，从受体不脱敏介导通道紊乱的角度揭示参与子痫前期血管功能失稳态的分子调控机理和关键节点。

Placental vascular dishomeostasis is the core of pathological changes of preeclampsia; however, the underlying mechanisms are unclear. From our previous original discovery, we found that the expressions of large-conductance calcium-activated potassium channels (BKCa) and voltage-gated potassium channels (KV), which can cause vasodilation, were decreased in placental vascular smooth muscle isolated from angiotensin II type 1 receptor (AT1R) autoantibodies (AT1-AA)-positive preeclamptic patients. This study intends to establish BKCa/KV knockout rat model, use patch clamp, single cell tension tester, etc. to clarify whether AT1-AA can inhibit the channels of BKCa/KV in placental vessel through sustained activation of AT1R-PLC-PKC pathway, which will result in increased preeclamptic placental vascular tension; then using radioactive ligand binding assay, fluorescence energy transfer technology, etc. to investigate the molecular mechanism of AT1-AA-induced non-desensitization of AT1R pathway in placental vascular smooth muscle from multiple aspects-decreased phosphorylation of AT1R, changes of vesicular formation proteins or transport proteins, abnormal receptor conformation and the rate of synthesis, reduced cell membrane fluidity. According to the general objectives--to inveatigate the dynamic regulating mechanism .of vascular homeostasis and remodeling this project aimed to reveal the molecular regulatory mechanisms and key node of preeclampsia vascular lesion from the perspective of receptor non-desensitization mediated channel disturbances.