Inactivation of the catecholamine transporter during the preparation of chromaffin granule membrane ‘ghosts’

FEBS Letters

Gasnier, Bruno¹  Henry, Jean-Pierre¹  Scherman, Daniel¹ 

[1] Unité de Neurobiologie Physico-Chimique, Institut de Biologie Physico-Chimique, 13, rue Pierre et Marie Curie, 75005 Paris, France

关键词: Monoamine transporter;    Chromaffin granule;    Tetrabenazine;    Reserpine;    Catecholamine;    Drug binding;    TBZ;    tetrabenazine;    TBZOH;    dihydrotetrabenazine (2-hydroxy-3-isobutyl-9;    10-dimethoxy-1;    2;    3;    4;    6;    7-hexahydro-11b(H) benzo [a] quinolizine);    [3H]TBZOH;    [2-3H]dihydrotetrabenazine;    RES;    reserpine;    ΔμH+;    proton electrochemical gradient;   

DOI  :  10.1016/0014-5793(87)80222-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The activity of the catecholamine transporter of chromaffin granules and the binding to these vesicles of reserpine, a transporter inhibitor, decrease during ghost preparation. In contrast, the number of binding sites of dihydrotetrabenazine, another transporter ligand, is constant. Dihydrotetrabenazine thus binds to an inactive transporter whereas reserpine binds only to active vesicles. Inactivation occurs during lysis of the granules, possibly because of an incomplete resealing. The turnover number of the transporter, determined by dividing the uptake activity by the density of dihydrotetrabenazine binding sites, has a maximal value (140 molecules/min) in intact granules. The reserpine to dihydrotetrabenazine binding ratio (10–25%) is an estimate of the proportion of correctly resealed vesicles.

【 授权许可】

Unknown