大鼠肾小球膜中B2-激肽受体样结合

B2-kinin receptor like binding in rat glomerular membranes.

作者信息

Bascands J L, Pécher C, Cabos G, Girolami J P

机构信息

INSERM U 133, Toulouse, France.

出版信息

Biochem Biophys Res Commun. 1989 Jan 16;158(1):99-104. doi: 10.1016/s0006-291x(89)80182-2.

DOI:10.1016/s0006-291x(89)80182-2

PMID:2536281

Abstract

Incubation of a radiolabeled bradykinin analog, [125I]-Tyr8-BK with a crude membrane preparation obtained from isolated rat glomeruli revealed a time dependent binding. The binding was saturable, reversible and was a linear function of protein membrane concentration. The radiolabeled Tyr8-BK bound to a single class of binding sites with an equilibrium dissociation constant (KD) of 3.9 +/_ 0.7 nM and a density (Bmax) of 31 +/- 5 fmol/mg protein. The BK-receptor complex was not affected by angiotensin II or by arginine vasopressin and atrial natriuretic factor. BK binding was reversed by bradykinin (Ki = 0.3 10(-9) M), and by other kinin analogs in the following order of potency: Lys-BK, Met-Lys-BK, Thi5,8-D Phe7-BK. However, Des-Arg9-BK had no effect on binding of the radiolabelled BK. These results are consistent with the presence of a B2-kinin like receptor in rat glomeruli.

摘要

将放射性标记的缓激肽类似物[125I]-Tyr8-BK与从分离的大鼠肾小球获得的粗制膜制剂一起温育，结果显示存在时间依赖性结合。该结合是可饱和的、可逆的，并且是蛋白质膜浓度的线性函数。放射性标记的Tyr8-BK与一类结合位点结合，其平衡解离常数（KD）为3.9±0.7 nM，密度（Bmax）为31±5 fmol/mg蛋白质。缓激肽受体复合物不受血管紧张素II、精氨酸加压素和心房利钠因子的影响。缓激肽（Ki = 0.3×10−9 M）以及其他激肽类似物按以下效力顺序可逆转BK结合：Lys-BK、Met-Lys-BK、Thi5,8-D Phe7-BK。然而，去-Arg9-BK对放射性标记的BK的结合没有影响。这些结果与大鼠肾小球中存在B2-激肽样受体一致。