论文部分内容阅读
在分散培养的新生大鼠皮层神经元标本上，用全细胞电压箝技术分析了自发兴奋性及抑制性突触后电流（ＥＰＳＣ／ＩＰＳＣ）的性质并观察了乙酰胆碱（ＡＣｈ）对它们的影响。ＥＰＳＣ与ＩＰＳＣ可分别被。ｎｏｎ－ＮＭＤＡ谷氨酸受体拮抗剂ＤＮＱＸ及ＧＡＢＡ＿Ａ受体拮抗剂ｂｉｃｕｃｕｌｌｉｎｅ所取消，说明它们分别由这两种受体所介导。ＡＣｈ在低浓度１μｍｏｌ／Ｌ时减低ＩＰＳＣ发生频率，但不改变其幅度分布；高浓度ＡＣｈ（１０一１００μｍｏｌ／Ｌ）增加ＥＰＳＣ的频率，也不改变其幅度分布。ＡＣｈ的效应可为Ｍ受体拮抗剂阿托品所取消，但它对外源性谷氨酸及γ氨基丁酸引起的全细胞电流无显著影响。以上结果表明，皮层神经元可通过维持不同ＡＣｈ水平来实现对其兴奋性及突触传递效率的精细调节。这一作用可能是通过作用于Ｍ受体，影响突触前递质释放来实现的。
The characteristics of spontaneous excitatory and inhibitory postsynaptic currents (EPSC / IPSC) were analyzed by whole cell voltage clamp technique and the effect of acetylcholine (ACh) on them was observed on cultured cortical neurons. EPSC and IPSC can be respectively. non-NMDA glutamate receptor antagonist DNQX and GABA_A receptor antagonist bicuculline canceled, indicating that they are mediated by these two receptors. ACh reduced the frequency of IPSC at a low concentration of 1μmol / L, but did not change its amplitude distribution. High concentration of ACh (10-100μmol / L) increased the frequency of EPSC without changing its amplitude distribution. The effect of ACh was abolished by the M receptor antagonist atropine, but it had no significant effect on whole cell currents induced by exogenous glutamate and gamma aminobutyric acid. The above results indicate that cortical neurons can finely adjust their excitability and synaptic transmission efficiency by maintaining different levels of ACh. This effect may be through the role of M receptor, affect the presynaptic transmitter release to achieve.