Development of trigeminal motoneuron

三叉神经运动神经元的发育

• 批准号: 11671838
• 负责人: INOUE Tomio
• 金额: $ 2.24万
• 依托单位: Showa University (2000)Osaka University (1999)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11671838/
• 关键词: trigeminal; motoneuron; calcium; slice; patch clamp; afterhyperpolarization; カルシウム電流; スパイク後過分極電位; A-キナーゼ

Feeding behavior of mammals changes from relatively simple sucking to complicated mastication during development. It should be very important that development of central neural mechanisms for feeding behavior is coordinated with the development of organs in oro-facial area. Trigeminal motoneurons play an important role in converting centrally organized masticatory drive to jaw movements. In the present study, we investigated developmental change of physiological properties of trigeminal motoneurons in rats age by using intracellular or patch clamp recordings. As we previously reported, application of 200 μM 5-HT suppressed the mAHP.Application of 25-200 μM 8-OH-DPAT, 5-HT_<1A> and 5-HT_7 receptor agonist, inhibited the mAHP dose-dependently. Application of pindolol, 5-HT_<1A> receptor antagonist failed to block 8-OH-DPAT-induced attenuation of the mAHP, whereas clozapine, dopamine D_2, 5-HT_<2A/2C> and 5-HT_7 receptor antagonist, antagonized both 5-HT- and 8-OH-DPAT-induced suppression of the mAHP.Ritanserin, 5-HT_<2A/2C> and 5-HT_7 receptor antagonist, also blocked 8-OH-DPAT-induced suppression of the mAHP.α-methyl-5-HT, 5-HT_<2A/2C> receptor agonist, did not attenuate the mAHP.The 8-OH-DPAT-induced suppression of the mAHP could be also antagonized by protein kinase A (PKA) inhibitor, H89. These results suggest that 5-HT-induced attenuation of the mAHP is mediated by 5-HT_7 receptors through activation of PKA in young adult rats. In contrast application of 10-100 μM 5-HT to trigeminal motoneurons of neonatal rats modulates low voltage activated (LVA) calcium currents. 5-HT lowered activation threshold, increases peak amplitude and decreases time to peak and τ_m of LVA currents. 8-OH-DPAT and 5-CT, a 5-HT_7 agonist, did not mimic the effects of 5-HT.We conclude that trigeminal motoneurons are modulated differently by 5-HT according to their age.

哺乳动物的摄食行为在发育过程中从相对简单的吸吮逐渐发展到复杂的咀嚼。摄食行为中枢神经机制的发育与口面部器官的发育协调是十分重要的。三叉神经运动神经元在将中枢组织化的咀嚼驱动转换为颌骨运动中起重要作用。本研究应用细胞内记录和膜片钳记录技术，观察了大鼠三叉神经运动神经元生理特性随年龄的发育变化。应用200 μM 5-HT抑制mAHP，应用25-200 μM 8-OH-DPAT（5-HT_7<1A>和5-HT_7受体激动剂）呈剂量依赖性抑制mAHP。应用5-HT_2受体<1A>拮抗剂吲哚洛尔不能阻断8-OH-DPAT对mAHP的抑制作用，而氯氮平、多巴胺D_2、5-HT_（2A/2C）和5-HT_7受体拮抗剂能阻断5-HT和8-OH-DPAT对mAHP的抑制作用，而5-HT_（2A/2C）和5-HT_7受体拮抗剂利坦色林也能阻断8-OH-DPAT对mAHP的抑制作用。5-HT_（2A/2C）受体激动剂不能抑制mAHP，而8-OH-DPAT对mAHP的抑制作用可被蛋白激酶A（PKA）抑制剂H89拮抗。结果提示5-HT诱导的mAHP衰减作用是通过5-HT_7受体激活PKA介导的。相反，10-100 μM 5-HT作用于新生大鼠三叉神经运动神经元可调节低电压激活（LVA）钙电流。5-HT降低LVA电流的激活阈值，增加峰值幅度，缩短达峰时间和τ m。8-OH-DPAT和5-HT_7激动剂5-CT不能模拟5-HT的作用。

项目成果

Hidaka O.: "Effects of serotonin on spike afterpotentials in rat jaw-closing motoneurons"J. Neurophysiol. 82. 2633-2640 (1999)

Hidaka O.：“血清素对大鼠下颌闭合运动神经元尖峰后电位的影响”J。

Inoue T.: "Symposium on Neurobiology of Mastication"Elsevier Science. 525 (1999)

Inoue T.：“咀嚼神经生物学研讨会”Elsevier Science。

Masuda, Y.: "Neuronal activity in the putamen and the globus pallidus of rabbit during mastication"Neurosci. Res.. 39. 11-19 (2001)

Masuda, Y.：“咀嚼过程中兔子壳核和苍白球的神经活动”Neurosci。

Masuda, Y et al.: "Neuronal activity in the putamen and the globus pallidus of rabbit during mastication."Neurosci.Res.. 39. 11-19 (2001)

Masuda, Y 等人：“咀嚼过程中兔子壳核和苍白球的神经活动。”Neurosci.Res.. 39. 11-19 (2001)

Inoue T.: "Contributions of protein kinase A and protein kinase C to serotonergic effects on post-spike afterhyperpolarization of jaw-closing motoneurons in the rat"Neurosci. Res.. S23. S55 (1999)

Inoue T.：“蛋白激酶 A 和蛋白激酶 C 对大鼠闭颌运动神经元尖峰后超极化的血清素能效应的贡献”Neurosci。