Differential regulation of μ‐opiate receptors in heroin‐ and morphine‐dependent rats

FEBS Letters

Rice, K.C.¹  Skolnick, P.¹  Bolger, G.T.¹  Weissman, B.A.¹ 

[1] Laboratory of Neuroscience, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA

关键词: Diacetylmorphine;    Opiate dependence;    Na+;    Morphine;    Tyr-D-Ala-Gly-Mephe-Gly-ol;   

DOI  :  10.1016/0014-5793(88)81294-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rats made dependent on heroin and morphine exhibit both qualitative and quantitative differences in the characteristics of radioligand binding to μ-opioid receptors in the central nervous system. In brain membranes prepared from control animals, [³H]dihydromorphine (DHM) binding was best described by a two-site model, while in morphine-dependent rats, [³H]DHM binding was best described by a single-site model. In contrast, [³H]DHM binding to membranes from heroin-dependent animals was best described by a two-site model, with an increased density of the high-affinity, and no change in the low-affinity population compared to controls. Furthermore, both the number of binding sites for [³H]DAGO (a ligand that selectively labels a population of high-affinity μ-opiate receptors) and the sensitivity of [³H]DHM to sodium ions was increased in heroin; but not in morphine-dependent rats. These studies demonstrate that opiate receptors are differentially regulated in heroin- and morphine-dependent animals. Such neurochemical changes in μ-opiate receptors may underlie differences in the behavioral and pharmacological profiles of heroin and morphine reported in man.

【 授权许可】

Unknown