Effect of neuropeptideY on the T-type Ca^<2+> channel current

神经肽Y对T型Ca^2通道电流的影响

基本信息

批准号：
15500254
负责人：
OKADA Masayoshi
金额：
$ 2.37万
依托单位：
Kansai Medical University (2004)Niigata University (2003)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

T-type Ca^<2+> channel plays pivotal roles in regulating the excitability of the neurons and non-neuronal excitable cells. The neuropeptideY (NPY) is one of the most abundantly expressed neuropeptides in the central and peripheral nervous systems, and its distribution correlates well with that of T-type Ca^<2+> channel, suggesting a functional interaction with it. The aim of this study was to investigate the functional interaction. In the former half of this study, I used the undifferentiated NG108-15 cells, in which the expression of the T-type Ca^<2+> channel current was confirmed. I found that low doses of NPY significantly augmented the T-type Ca^<2+> channel current with whole cell patch-clamp technique using Ba^<2+> as the charge carrier. The NPY treatment shifted the I-V relationship negatively. Experiments using NPY receptor subtype-selective agonist/antagonists revealed that both Y_1 and Y_2 receptors additively involved in the augmentation of the current. Consistently, RT-PCR analysis showed the expressions of mRNAs for Y_1 and Y_2 receptors. In the later half, to investigate the functional interaction, which was shown in the NG 108-15 cells, in the brain preparation, I set up culture system of hippocampal slice, which was reported to express the proteins. I examined the voltage-dependent channel currents expressed in the CA1 pyramidal neurons with slice patch-clamp technique. Further work is needed to obtain the conclusion of the NPY's effect on the voltage-dependent channel currents.

T型Ca 2+ 通道在调节神经元和非神经元可兴奋细胞的兴奋性中起关键作用。神经肽Y(NPY)是中枢和周围神经系统中表达最丰富的神经肽之一，其分布与T型Ca ^ 2+ 通道的分布密切相关，表明与其存在功能性相互作用。本研究的目的是研究功能相互作用。在本研究的前半部分中，我使用了未分化的NG108-15细胞，其中确认了T型Ca^2+通道电流的表达。我发现低剂量的NPY通过使用Ba^2+作为电荷载体的全细胞膜片钳技术显着增强了T型Ca^2+通道电流。 NPY 治疗使 I-V 关系发生负向改变。使用 NPY 受体亚型选择性激动剂/拮抗剂的实验表明，Y_1 和 Y_2 受体都额外参与电流的增强。 RT-PCR 分析一致显示 Y_1 和 Y_2 受体 mRNA 的表达。在后半部分，为了研究在大脑制备中 NG 108-15 细胞中显示的功能相互作用，我建立了海马切片的培养系统，据报道该系统可以表达蛋白质。我用切片膜片钳技术检查了 CA1 锥体神经元中表达的电压依赖性通道电流。需要进一步的工作来得出 NPY 对电压依赖通道电流的影响的结论。