Function of Receptors of neuroactive Substances in the ascending neurons conveying oro-facial, visceral and derma pain

上行神经元中神经活性物质受体传递口面部、内脏和真皮疼痛的功能

• 批准号: 10671733
• 负责人: HAYASHI Haruhide
• 金额: $ 1.98万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10671733/
• 关键词: NK-1 receptor; nociceptive neuron; C-fiber response; spinal dorsal horn; pain; substance P; chronic information animal; spinothalamic neuron; サブスタレスP; NK-1 受容体; 下行抑制; 大縫線核

The effects of local spinal application of new, specific NK-1 receptor antagonist for rodents, RP-67580 on the electrically-evoked late discharges of spinothalamic and non-projection neurons in the rat superficial spinal dorsal horn were examined.Under pentobarbital sodium anesthesia, single-unit recordings were made from the nociceptive neurons in lamina I of the lumber spinal cord. They were tested for the projections to thalamus and cervical cord (C3) and for the late discharges evoked by electrical stimulation of the receptive fields. Doses of 0.4-37 nmol of RP-67580 were applied directly onto the cord surface close to the recording site. Drug effects were examined every 10-30 min for 30-180 min. they also were tested for the effects of NRM electrical stimulations (a train of 20 pulses, 0.2 ms duration, 40Hz).The rate discharges of majority of non-projection neurons were inhibited by the application of RP-67580. On the other hand, the responses of the majority of spinothalamic neurons were not affected or rather increased. A significant relationship was found between the magnitudes of maximum inhibitions by the antagonist and NRM stimulation (correlation 0.73).This study demonstrated that RP-67580 inhibited the C-evoked discharges of the nonprojection neurons selectively. The results suggest that the role of SP was different between the spinothalamic and non-projection neurons, and that SP plays an important role in nociceptive transmission or modulation mediated by primary afferent C-fibers mainly in the interneurons in normal acute pain. This study also demonstrated that the nociceptive responses mediated by NK-1 receptor are inhibited by NRM stimulation.

在戊巴比妥钠麻醉下，观察了局部应用新型啮齿类特异性NK-1受体拮抗剂RP-67580对大鼠脊髓背角浅层脊髓丘脑和非投射神经元电诱发晚放电的影响。测试它们向丘脑和颈髓（C3）的投射以及电刺激感受野诱发的迟发放电。将0.4-37 nmol剂量的RP-67580直接应用于靠近记录部位的脐带表面。每隔10-30分钟检查一次药物作用，持续30-180分钟。还测试了NRM电刺激（20个脉冲串，0.2 ms持续时间，40 Hz）的作用。大多数非投射神经元的频率放电被RP-67580抑制。另一方面，大多数脊髓丘脑神经元的反应不受影响，而是增加。拮抗剂的最大抑制幅度与刺激NRM有显著的相关性（相关系数0.73），表明RP-67580选择性地抑制非投射神经元的C诱发放电。结果提示，SP在脊髓丘脑和非投射神经元中的作用不同，在正常急性痛时，SP主要在中间神经元中参与初级传入C纤维介导的伤害性感受传递或调制。本研究还证实，刺激NRM可抑制NK-1受体介导的伤害性反应。

项目成果

H. Hayashi, Fei Zhao: "Role of NK-1 receptor during inhibition by raphe magnus stimulation in the lamina I spinal dorsal horn neurons"Abstracts 9th World Congress on Pain. 9. (1999)

H. Hayashi、Fei Chao：“NK-1 受体在中缝大肌刺激抑制 I 层脊髓背角神经元过程中的作用”，第九届世界疼痛大会摘要。