beta-endorphin: characteristics of binding sites in the rabbit cerebellar and brain membranes.
beta-endorphin: characteristics of binding sites in the rabbit cerebellar and brain membranes.
复制标题
β-内啡肽：兔小脑和脑膜结合位点的特征。
DOI：
10.1016/0006-291x(83)91412-2
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发表时间：
1983
影响因子：
3.1
通讯作者：
Li,CH
中科院分区：
文献类型：
--
作者：
Ho,CL;HammondsJr,RG;Li,CH
以[3 H2 Tyr 27] β h内啡肽为主要配体，测定了人β-内啡肽与兔小脑和脑细胞膜的特异性结合。在这两种组织中的结合是时间依赖性和饱和的，在小脑和大脑中的表观平衡解离常数分别为0.275 nM和0.449 nM。小脑的结合能力大于大脑。动力学研究表明，小脑和大脑的结合速率常数分别为2.7× 10 7 M− 1 min− 1和2.4× 10 7 M− 1 min− 1。氚化β h-内啡肽从小脑和脑中的解离与来自单个位点的一级衰变不一致。在小脑中，这些是缓慢解离复合物的时间依赖性增加。测定了几种阿片肽和阿片剂抑制氚化β h-内啡肽结合的效力。偏爱μ、δ和κ阿片受体的配体（吗啡、甲硫啡肽和乙基酮环唑辛）对脑和小脑膜中的β h-内啡肽位点都具有相似的亲和力。
Specific binding of human β-endorphin to rabbit cerebellar and brain membranes was measured using [3 H 2-Tyr 27]-β h-endorphin as the primary ligand. In both tissues binding was time dependent and saturable, with apparent equilibrium dissociation constants of 0.275 nM and 0.449 nM in the cerebellum and brain, respectively. The binding capacity of cerebellum is greater than that of brain. Kinetic studies showed that the association rate constants were 2.7× 10 7 M− 1 min− 1 for cerebellum and 2.4× 10 7 M− 1 min− 1 for brain. Dissociation of tritiated β h-endorphin from both cerebellum and brain is not consistent with a first order decay from a single site. In the cerebellum, these is a time-dependent increase in slowly dissociating complex. The potency of several opioid peptides and opiates to inhibit the binding of tritiated β h-endorphin was determined. Ligands with preference for μ, δ, and κ opiate receptor (morphine, Metenkephalin and ethylketocyclazocine) all have similar affinities toward β h-endorphin sites in both brain and cerebellar membranes.