摘要
甘丙肽是1983年发现的一种脑肠肽,与认知情感和内稳态的调节密切相关。本文着重综述了甘丙肽对多种学习记忆功能的抑制及调节学习记忆功能的机制:甘丙肽的过度表达破坏了学习记忆相关部位去甲肾上腺素、5-羟色胺和乙酰胆碱的平衡,使学习记忆功能处于病理状态;兴奋胆碱能M2突触前受体,反馈性减少乙酰胆碱释放;引起神经细胞膜超极化及外向性钾离子流,产生抑制性突触后电位,抑制乙酰胆碱释放;降低突触前膜兴奋性谷氨酸释放,损伤突触可塑性;甘丙肽受体是G蛋白偶联受体,甘丙肽在受体活化下游抑制腺苷酸化环化酶及转录因子CREB结合启动子,影响新的基因和蛋白表达,从而阻断短时记忆转入长时记忆。临床上在阿尔茨海默病和Down’s综合征等神经变性性疾病中,围绕Meynert基底核和斜角带核胆碱能神经元周围甘丙肽纤维和终末数量大大增加,提示使用甘丙肽拮抗剂治疗的可能。
Galanin is a brain-gut peptide discovered in 1983, which is corr elated with the regulation of cognitive affection and entatic state homeostasis. The article reviewed the function and mechanism of galanin in inhibiting learni ng-memory. The overexpression of galanin breaks the balance among noradrenalin, 5-hydroxytryptamine and acetylcholine in the locations of learning memory, and u ltimately impaires learning memory. On the other hand, it reduces the release of acetylcholine by exciting presynaptic M2 receptor, and injures synaptic plastic ity by lowering evoked glutamate release. Galanin receptor, as a G-protein coupl ed receptors, downregulates the expression of new gene and protein expression an d thus blocks short-term memory into long-term memory, by inhibiting adenylate c yclase and transcription factor CREB to bind to promotor at the downstream of re ceptor activiation. The number of galanin nerve fibres and terminals surrounding Meynert basal nucleus and diagonal band of broca increases in such neural degen erative diseases as Alzheimer's disease and Down's syndrome, which suggests the possibility of galanin antagonist therapy.
出处
《中华神经医学杂志》
CAS
CSCD
2005年第5期538-540,共3页
Chinese Journal of Neuromedicine
关键词
甘丙肽
学习
记忆
神经递质
信号转导
Galanin
Learning
Memory
Neurotransmitters
Signal transduction
