De Vos H, Convents A, De Keyser J, De Backer J P, Van Megen I J, Ebinger G, Vauquelin G
Department of Protein Chemistry, Vrije Universiteit Brussel, St. Genesius-Rode, Belgium.
Brain Res. 1991 Dec 6;566(1-2):13-20. doi: 10.1016/0006-8993(91)91675-q.
The regional distribution of [3H]idazoxan and [3H]rauwolscine was studied autoradiographically in human brain. [3H]Idazoxan binds with high affinity to alpha 2 adrenoceptors as well as to non-adrenergic sites (NAIBS). [3H]Rauwolscine, besides binding to alpha 2 adrenoceptors, also binds to 5-HT1A receptors. Both radioligands labelled the same population of alpha 2 adrenoceptors, defined as the epinephrine-displaceable binding component. The highest densities of alpha 2 adrenoceptors occur in the leptomeninges, cerebral cortex and claustrum; lower densities were visualised in the basal ganglia, thalamus, pons, substantia nigra, cerebellum and medulla oblongata; no alpha 2 adrenoceptors were detected in amygdala and nucleus ruber. NAIBS were present in all the examined brain areas, with the highest densities found in the basal ganglia and substantia nigra. The finding that certain brain regions, such as the amygdala, contained NAIBS but no detectable alpha 2 adrenoceptors, suggests that the binding sites are independent from each other. The regional distribution of 5-HT1A receptors labelled by [3H]rauwolscine is in agreement with previous studies using [3H]8-OH-DPAT.
采用放射自显影法研究了[3H]咪唑克生和[3H]萝芙木碱在人脑内的区域分布。[3H]咪唑克生对α2肾上腺素能受体以及非肾上腺素能位点（NAIBS）具有高亲和力。[3H]萝芙木碱除了与α2肾上腺素能受体结合外，还与5-HT1A受体结合。两种放射性配体标记的是同一群α2肾上腺素能受体，定义为肾上腺素可置换结合成分。α2肾上腺素能受体密度最高的部位是软脑膜、大脑皮质和屏状核；基底神经节、丘脑、脑桥、黑质、小脑和延髓的密度较低；杏仁核和红核未检测到α2肾上腺素能受体。NAIBS存在于所有检测的脑区，基底神经节和黑质的密度最高。某些脑区如杏仁核含有NAIBS但未检测到α2肾上腺素能受体，这一发现表明这些结合位点相互独立。[3H]萝芙木碱标记的5-HT1A受体的区域分布与先前使用[3H]8-羟基二丙胺甲苯磺酸盐的研究结果一致。
