突触黏附分子β-neurexin和neuroligin 1在蛛网膜下腔出血后认知障碍中的作用机制研究

蛛网膜下腔出血（SAH）后认知障碍是影响预后的重要因素，发生机制不明。突触及其可塑性是形成认知的基础，突触之间的信号传递依赖于突触黏附分子的互相作用，本研究着重探索突触黏附分子β-neurexin（主要位于突触前膜）和neuroligin 1（主要位于突触后膜）在SAH后认知障碍中的作用。第一部分围绕细胞层面展开，在SAH体外模型中，通过基因转染和RNAi调控目标基因，结合单细胞膜片钳技术，了解神经元突触形态学、超微结构、电生理改变；第二部分围绕组织层面展开，通过活体脑片膜片钳技术，结合基因调控，评估海马神经通路长时程增强（LTP）；第三部分围绕活体动物SAH模型展开，应用转基因和siRNA干预等方法，观察突触功能、数量，以及LTP的变化，检测认知障碍的程度。本研究纵向从细胞、组织和活体三个层面，横向从超微结构、电生理和分子生物学三个层面开展研究，将为改善SAH预后提供新思路和理论依据。

Cognitive impairment after subarachnoid hemorrhage (SAH) is an important factor affecting the prognosis of patients. The mechanism is unknown at present. Neuronal transmission relies on signals transmitted through a vast array of excitatory and inhibitory neuronal synaptic connections. There is a wealth of evidence suggesting that cell adhesion molecules provide much of the information required for synapse formation. This project focused on exploring the roles of synaptic adhesion molecules β-neurexin and neuroligin 1 in cognitive impairment after SAH. Firstly, we try to discover the mechanism in cell. Gene transfection and RNAi are used to regulate the target genes expression, and then to understand synaptic morphology, ultrastructure, and electrophysiological characteristics change. Secondly, in brain slice from different genetic backgrounds, we use patch-clamp technique to study LTP change in hippocampus C1-C3 areas and dentate gyrus pathways. Finally, SAH model is established in transgenic mice and drug treated rats, and then we observe the changes of synaptic function, synapsis quantity, and LTP, and assess the cognitive impairment. The longitudinal studies from three levels of cell, tissue and in vivo, horizontal researches from three levels of ultrastructure, electrophysiology and molecular biology in this study will provide us new ideas and theoretical basis to improve the prognosis of SAH.