Quirion R, Shults C W, Moody T W, Pert C B, Chase T N, O'Donohue T L
Nature. 1983;303(5919):714-6. doi: 10.1038/303714a0.
Among various neuropeptides present in the central nervous system (CNS), substance P, an undecapeptide, is of great interest as a putative pain neurotransmitter. Substance P is present within numerous intrinsic neural pathways throughout the CNS. Several groups have attempted to label substance P receptors on brain membranes by ligand binding techniques; only one study used native 3H-labelled substance P as the ligand and the precise anatomical distribution of substance P receptors has not yet been described. Here we report the autoradiographic localization of 3H-labelled substance P receptors in rat brain using the in vitro autoradiographic technique developed recently. 3H-substance P binds specifically to an apparently single class of sites on slide-mounted brain sections (Kd = 0.52 nM; Bmax = 21.6 fmol per mg protein). The ligand selectivity pattern suggests that 3H-substance P binding sites are similar to those found in other assays. 3H-substance P receptors are highly concentrated in the external layers of the olfactory bulb, medial amygdala, dentate gyrus, superior colliculus, dorsal parabrachial nucleus and locus coeruleus, with moderate densities being found in the nucleus accumbens, striatum, periaqueductal grey and subiculum. The distribution of 3H-substance P receptors suggests that substance P is probably involved in the control of sensory processes such as pain, vision, audition and olfaction.
在中枢神经系统（CNS）中存在的各种神经肽中，P物质，一种十一肽，作为一种假定的疼痛神经递质备受关注。P物质存在于整个中枢神经系统的众多内在神经通路中。几个研究小组试图通过配体结合技术标记脑膜上的P物质受体；只有一项研究使用天然3H标记的P物质作为配体，且P物质受体的精确解剖分布尚未得到描述。在此，我们报告使用最近开发的体外放射自显影技术对大鼠脑中3H标记的P物质受体进行放射自显影定位。3H-P物质特异性结合于载玻片上脑切片上的一类明显单一的位点（解离常数Kd = 0.52 nM；最大结合量Bmax = 每毫克蛋白质21.6 fmol）。配体选择性模式表明3H-P物质结合位点与其他检测中发现的位点相似。3H-P物质受体高度集中在嗅球外层、杏仁核内侧、齿状回、上丘、臂旁背核和蓝斑，伏隔核、纹状体、导水管周围灰质和海马下托中密度适中。3H-P物质受体的分布表明P物质可能参与疼痛、视觉、听觉和嗅觉等感觉过程的控制。
