Kohzuki M, Chai S Y, Paxinos G, Karavas A, Casley D J, Johnston C I, Mendelsohn F A
Austin Hospital, Department of Medicine, University of Melbourne, Heildelberg, Victoria, Australia.
Neuroscience. 1991;42(1):245-60. doi: 10.1016/0306-4522(91)90162-h.
Endothelin binding sites in rat brain were mapped by quantitative in vitro autoradiography employing [125I]endothelin-1 as radioligand. [125I]Endothelin-1 bound with high affinity and specificity to rat cerebellar sections and was potently displaced by unlabelled endothelins (endothelin-1 greater than endothelin-2 = endothelin-3) and sarafotoxin 6B. The highest densities of endothelin binding sites were found in the cerebellum (especially Purkinje cell layer), choroid plexus and median eminence. High densities were found in the supraoptic and paraventricular hypothalamic nuclei, anterior hypothalamic area, ventromedial hypothalamic nucleus, mammillary nuclei and glomerular layer of olfactory bulb. Moderate densities were found in many thalamic nuclei, the pretectal region, interpeduncular nucleus, suprachiasmatic nucleus, raphe nuclei, tegmental nuclei, olfactory ventricle, red nucleus, subthalamic nucleus, central gray, reticular nuclei, vestibular nuclei, oculomotor and trochlear nuclei, hypoglossal nucleus, motor trigeminal nucleus, nucleus of the trapezoid body and lateral cerebellar nucleus. Low but detectable densities of endothelin binding sites were found in medial geniculate nucleus, fields of Ammon's horn, caudate-putamen, globus pallidus, entopeduncular nucleus, substantia nigra, anterior commissure, internal capsule, anterior pituitary, median preoptic nucleus, septohypothalamic nucleus, superior colliculus and area postrema. These patterns were completely abolished by 1 microM unlabelled endothelin-1, -2 and -3 and sarafotoxin S6B. Brain endothelin binding sites show high affinity for endothelin-1, -2 and -3 and sarafotoxin 6B with highest affinity for endothelin-1. Endothelin binding sites show a non-vascular pattern of distribution in the brain, suggesting that the peptide may have widespread functions as a modulator of neuronal function.
采用[125I]内皮素-1作为放射性配体，通过定量体外放射自显影法对大鼠脑中的内皮素结合位点进行了定位。[125I]内皮素-1与大鼠小脑切片具有高亲和力和特异性结合，并且能被未标记的内皮素（内皮素-1＞内皮素-2 = 内皮素-3）和铃蟾肽6B有效取代。在内皮素结合位点密度最高的区域是小脑（尤其是浦肯野细胞层）、脉络丛和正中隆起。视上核和室旁下丘脑核、下丘脑前区、下丘脑腹内侧核、乳头体核以及嗅球的肾小球层也发现有高密度结合位点。许多丘脑核、顶盖前区、脚间核、视交叉上核、中缝核、被盖核、嗅脑室、红核、丘脑底核、中央灰质、网状核、前庭核、动眼神经核和滑车神经核、舌下神经核、运动三叉神经核、梯形核和小脑外侧核中结合位点密度中等。在内侧膝状体、海马角、尾状核-壳核、苍白球、内苍白球核、黑质、前连合、内囊、垂体前叶、视前正中核、隔下丘脑核、上丘和最后区中发现了低密度但可检测到的内皮素结合位点。这些分布模式可被1 microM未标记的内皮素-1、-2和-3以及铃蟾肽S6B完全消除。脑内皮素结合位点对内皮素-1/-2和-3以及铃蟾肽6B具有高亲和力，其中对内皮素-1的亲和力最高。脑内皮素结合位点在脑中呈现非血管分布模式，这表明该肽可能作为神经元功能调节剂具有广泛的功能。
