N-甲基天冬氨酸受体拮抗剂AP-5在海马对兔P3波电位的作用

Effects of AP5,an antagonist to NmethyDasparate receptor on rabbit's P3 potentials

目的推测Ｎ甲基天冬氨酸受体（ＮｍｅｔｈｙｌＤａｓｐａｒａｔｅｒｅｃｅｐｔｏｒ，ＮＭＤＡＲ）的兴奋性突触后电位（ｅｘｃｉｔａｔｏｒｙｐｏｓｔｓｙｎａｐｔｉｃｐｏｔｅｎｔｉａｌｓ，ＥＰＳＰ）活动对兔Ｐ３波的作用。方法采用ＮＭＤＡＲ竞争性拮抗剂ＡＰ５（３．１２５、６．２５、１２．５ｍｍｏｌ／Ｌ）在海马ＣＡ１、ＣＡ３微量注入，观察Ｐ３波电位变化。结果ＡＰ５在ＣＡ１区呈一定量效依赖延长Ｐ３ａ波潜伏期，在ＣＡ１、ＣＡ３为明显量效依赖延长Ｐ３ｂ波潜伏期，ＡＰ５对Ｐ３ａ、Ｐ３ｂ波电压振幅无明显影响。结论ＣＡ１区ＮＭＤＡＲＥＰＳＰ活动是Ｐ３ａ波发生相关神经元兴奋的易化因素，可能是海马实施对Ｐ３ａ波潜伏期调节的重要机制。ＣＡ１、ＣＡ３区ＮＭＤＡＲＥＰＳＰ可能共同对Ｐ３ｂ波发生相关神经元兴奋起易化作用，故可影响其潜伏期。

Objective The regulatory effects of NmethyDasparate receptor (NMDAR) on P3 were Medical studied in CA1 or CA3. Methods Rabbits'P3 in Pz place were recorded in auditory oddball paradigm. Bilateral CA1 or CA3 of rabbits' were microinfusied with Ap5(3.12512.5mmol/l), an antogonist of NMDAR respectively. Results P3a latency was increased with AP5 dosedependent pattern in CA1, P3b latency was prolonged by AP5 in CA1 and CA3 as well. Conclusions NMDAR EPSP in CA1 and CA3 produced a facilitory role in exciting neurons producing P3b. Additionally,NMDAR EPSP in CA1 plays the same role as above of P3a,which may be a key pathway for hippocampus to regulate P3a.