Alpha-2 adrenergic receptor subtypes indicated by [3H]yohimbine binding in human brain.
Alpha-2 adrenergic receptor subtypes indicated by [3H]yohimbine binding in human brain.
复制标题
[3H]育亨宾在人脑中的结合表明α-2肾上腺素能受体亚型。
DOI：
10.1016/0024-3205(86)90212-2
复制
发表时间：
1986
期刊：
影响因子：
6.1
通讯作者：
Bylund,DB
中科院分区：
文献类型：
--
作者：
Petrash,AC;Bylund,DB
哺乳动物α -2肾上腺素能受体在不同组织和物种中的药理学特征为α -2肾上腺素能受体存在两种亚型提供了证据。Prazosin和oxymetazoline已被证明在大鼠组织中区分受体亚型。为了确定这两种受体亚型在人脑中的相对比例，我们研究了氧美唑啉和吡唑嗪对α -2肾上腺素能拮抗剂[3H]育亨宾结合的抑制作用。大脑皮层和小脑膜的抑制曲线与一类受体结合位点一致，表明这两个大脑区域只包含两种亚型中的一种。该亚型具有α - 2a肾上腺素能亚型（育亨宾≥oxymetazoline⪢prazosin）的药理学特征。相比之下，这两种配体在人类尾状核中的抑制曲线与两类结合位点的比例大致相等的模型一致，这表明该组织含有α - 2a和α - 2b肾上腺素能受体亚型的密度大致相等。
Pharmacologic characterization of mammalian alpha-2 adrenergic receptors in various tissues and species has provided evidence for the existence of two alpha-2 adrenergic receptor subtypes. Prazosin and oxymetazoline have been shown to differentiate between the receptor subtypes as defined in rat tissues. In order to determine the relative proportions of these two receptor subtypes in human brain, the inhibition of the binding of the alpha-2 adrenergic antagonist [3H]yohimbine by oxymetazoline and prazosin was studied in membranes from three brain regions. Inhibition curves in membranes from the cerebral cortex and cerebellum were consistent with a single class receptor binding sites suggesting that these two brain regions contain only one of the two subtypes. This subtype has the pharmacologic characteristics of the alpha-2A adrenergic subtype (yohimbine ≥ oxymetazoline ⪢ prazosin). In contrast, inhibition curves for both ligands in the human caudate nucleus were consistent with a model of two classes of binding sites in approximately equal proportions, suggesting that this tissue contains approximately equal densities of the alpha-2A and alpha-2B adrenergic receptor subtypes.