Walker J M, Thompson L A, Frascella J, Friederich M W
Eur J Pharmacol. 1987 Jan 28;134(1):53-9. doi: 10.1016/0014-2999(87)90130-0.
Single unit extracellular recording was carried out in rats to compare the actions of a mu receptor agonist (morphine) to a kappa receptor agonist (U50,488) in the substantia nigra pars compacta (SNC). Intravenously administered morphine and U50,488 exhibited opposite effects: morphine excited SNC dopamine cells, and U50,488 inhibited them. Both effects were blocked by naloxone, although significantly more naloxone was necessary to block the effect of the kappa agonist. Local administration of U50,488 in the caudate also inhibited the firing of SNC dopamine cells. These results are discussed in terms of the natural functions of the prodynorphinergic straiatonigral projection.
在大鼠中进行了单单位细胞外记录，以比较μ受体激动剂（吗啡）和κ受体激动剂（U50,488）在黑质致密部（SNC）的作用。静脉注射吗啡和U50,488表现出相反的作用：吗啡兴奋SNC多巴胺能细胞，而U50,488抑制它们。两种作用均被纳洛酮阻断，尽管阻断κ激动剂的作用需要显著更多的纳洛酮。在尾状核局部注射U50,488也抑制SNC多巴胺能细胞的放电。根据前强啡肽能纹状体黑质投射的自然功能对这些结果进行了讨论。
