Jessop D S, Chowdrey H S, Lightman S L
Neuroendocrinology Unit, Westminister Hospital, London, UK.
Neuropeptides. 1990 Nov;17(3):135-40. doi: 10.1016/0143-4179(90)90076-b.
We have used specific radioimmunoassays coupled with reversed-phase high-performance liquid chromatography (HPLC) to measure and characterise substance P (SP) and substance K (SK) in subdivisions of the rat hypothalamus. SP and SK levels in the paraventricular nucleus (PVN) were 968 +/- 61 and 381 +/- 22 pg respectively; in the supraoptic nucleus (SON) were 210 +/- 21 and 79 +/- 8 pg; and in the median eminence/arcuate nucleus (ME) were 1044 +/- 66 and 451 +/- 20 pg. Reversed-phase HPLC revealed that immunoreactive (ir) SP was present solely in the non-oxidised form in all tissue extracts. The principal form of ir-SK in the PVN and SON coeluted with synthetic SK on HPLC, but some immunoreactivity eluted in a later position. This material represented less then 5% of the total ir-SK in extracts of the PVN and SON, but increased to 35-40% of the total in the ME. Gel chromatography and HPLC characterised this compound as being slightly smaller and more hydrophobic than SK. These results establish that ir-SK is present within the hypothalamus in varying amounts and molecular forms. The location of significant amounts of both SP and SK in the PVN and ME, the principal regions of CRF-41 synthesis and release, is compatible with a role for neurokinins in the modulation of CRF-41 and consequently ACTH release.
我们采用特异性放射免疫分析法结合反相高效液相色谱法（HPLC）来测定和表征大鼠下丘脑各亚区中的P物质（SP）和K物质（SK）。室旁核（PVN）中的SP和SK水平分别为968±61和381±22 pg；视上核（SON）中的水平分别为210±21和79±8 pg；而在正中隆起/弓状核（ME）中的水平分别为1044±66和451±20 pg。反相HPLC显示，在所有组织提取物中，免疫反应性（ir）SP仅以非氧化形式存在。PVN和SON中ir-SK的主要形式在HPLC上与合成SK共洗脱，但一些免疫反应性在较晚位置洗脱。这种物质在PVN和SON提取物中占总ir-SK的比例不到5%，但在ME中增加到总ir-SK的35 - 40%。凝胶色谱法和HPLC将该化合物表征为比SK略小且疏水性更强。这些结果表明，ir-SK以下丘脑内不同的量和分子形式存在。SP和SK在CRF - 41合成与释放的主要区域PVN和ME中大量存在，这与神经激肽在调节CRF - 41进而调节促肾上腺皮质激素释放中的作用是相符的。
