Cui Qiao-Ling, Yung Wing-Ho, Xue Yan, Chen Lei
Department of Physiology, Faculty of Medicine, Qingdao University, Qingdao, Shandong, China.
Eur J Neurosci. 2007 Oct;26(7):1853-61. doi: 10.1111/j.1460-9568.2007.05803.x. Epub 2007 Sep 14.
Substance P is a member of the neurokinin family. Previous studies have reported the existence of substance P and its high-affinity receptor, neurokinin-1 receptor, in globus pallidus. Employing in vivo extracellular recording combined with behavioural tests, the effects of substance P in globus pallidus of rats were studied. Micropressure ejection of the selective neurokinin-1 receptor agonist [Sar9,Met(O2)11] substance P increased the spontaneous firing rate of pallidal neurons in a concentration-dependent manner, with increases of 27.3% at 0.01, 33.4% at 0.03, 45.5% at 0.1, 38.4% at 0.3 and 36.4% at 1.0 mm. The selective neurokinin-1 receptor antagonist SR140333B prevented the excitatory effects induced by [Sar9,Met(O2)11] substance P. In behaving rats, we observed the postural effects of neurokinin-1 receptor activation in the globus pallidus. Consistent with electrophysiological results, unilateral microinjection of [Sar9,Met(O2)11] substance P (0.1 mm) led to a SR140333B-sensitive contralateral deflection in the presence of systemic haloperidol administration. Combining electrophysiological and behavioural findings, we concluded that substance P produces excitatory effects on globus pallidus neurons via neurokinin-1 receptors.
P物质是神经激肽家族的一员。先前的研究报道在苍白球中存在P物质及其高亲和力受体——神经激肽-1受体。采用体内细胞外记录结合行为测试的方法，研究了P物质在大鼠苍白球中的作用。选择性神经激肽-1受体激动剂[Sar9,Met(O2)11]P物质的微压喷射以浓度依赖的方式增加了苍白球神经元的自发放电率，在0.01mm时增加27.3%，0.03mm时增加33.4%，0.1mm时增加45.5%，0.3mm时增加38.4%，1.0mm时增加36.4%。选择性神经激肽-1受体拮抗剂SR140333B可阻断[Sar9,Met(O2)11]P物质诱导的兴奋作用。在行为学实验的大鼠中，我们观察到苍白球中神经激肽-1受体激活后的姿势效应。与电生理结果一致，在全身给予氟哌啶醇的情况下，单侧微量注射[Sar9,Met(O2)11]P物质（0.1mm）会导致对侧偏斜，且该效应可被SR140333B阻断。综合电生理和行为学研究结果，我们得出结论：P物质通过神经激肽-1受体对苍白球神经元产生兴奋作用。
