新型N-型钙通道抑制剂的发现、优化及作用机理研究

N-型钙通道调控脊柱背角I及II的突触前神经末端等的神经递质释放，是治疗病理性慢性疼痛、炎症痛、异常疼等重要靶点。前期我们首次发现来自我国南海芋螺的一个α-芋螺镇痛多肽T5对人胚肾细胞HEK293表达的N-型钙通道具有较高活性，但对神经元烟碱型乙酰胆碱受体亚型很弱。本课题拟在已有工作的基础上，应用膜片钳、分子生物学、分子计算模拟及慢性疼痛模型等，开展该新型N-型钙通道抑制剂对GABAb介导的N-型钙通道、其他钙通道等的选择性及对有关镇痛信号通路的影响，阐明其与ω-芋螺多肽型N-型钙通道抑制剂的作用机制区别，进一步筛选其他α-芋螺多肽、非ω-芋螺多肽是否也作用于N-型钙通道，并结合α-、ω-芋螺多肽型抑制剂与N-型钙通道作用的分子模拟结果，优化特异作用于新型N-型钙通道抑制剂或作用于神经元型乙酰胆碱受体亚型及N-型钙通道的多靶点抑制剂，以期获得对慢性疼痛镇痛活性更高先导化合物。

N-type calcium channel modulates the release of neurotransmitters in the pre-synaptic nerve terminals in lamina I and II of the dorsal horn of the spinal cord, and is the important target for the analgesics of neuropathic pain, inflammatory pain, allodynia and hyperalgesia. Recently, a potent analgesic alpha-conopeptide T5, which derived from Conus snail of China South Sea, have been firstly found to be a potent blocker of N-type calcium channel expressed in human embryonic kidney cell HEK 293, but it is weak for neuronal nicotinic acetylcholine receptors (nAChR). On the base of the above discovery, this project will use several methods, such as patch-clamp technique, molecular biology, molecular docking and dynamics simulations and chronic pain models, to investigate the selectivity of T5 to GABAb receptor-mediated N-type calcium channels and other voltage-dependent calcium channels and its effects on some typical signal molecules involved in pain, and elucidate the difference of this kind of N-type calcium channel inhibitors from omega-conopeptide N-type calcium channel inhibitors. This project will also screen new N-type calcium channel inhibitors among other alpha-conopeptides and other conopeptides that do not belong to omega-conopetides. Based on the structures of new N-type calcium channel inhibitors and molecular simulations, the structures of specific N-type calcium channel inhibitors and bifunctional inhibitors for N-type calcium channel and nAChR subtypes, such as alpha3beta2 and alpha9alpha10, will be optimized.After this work, the highly potent analgesics for chronic pain will be found.