Lew R, Summers R J
Br J Pharmacol. 1985 Jun;85(2):341-8. doi: 10.1111/j.1476-5381.1985.tb08867.x.
The distribution of beta-adrenoceptor subtypes in slide-mounted sections of guinea-pig kidney has been examined by the technique of in vitro labelling combined with autoradiography. Binding of (-)-[125I]-cyanopindolol (Cyp) to kidney sections equilibrated and dissociated slowly, was saturable and stereoselective with respect to the isomers of propranolol and pindolol. These characteristics were appropriate for binding to beta-adrenoceptors. Delineation of beta-adrenoceptor subtypes was achieved by use of betaxolol (beta 1-adrenoceptors) and ICI 118,551 (beta 2-adrenoceptors) and computer assisted curve fitting techniques. Both beta 1- and beta 2-adrenoceptors were present in the proportions 1:2. 3H-Ultrofilm images of (-)-[125I]-Cyp binding to guinea-pig kidney sections showed localized patches of binding in the cortex and concentrated binding in the outer stripe of the medulla. Cortical receptors were of the beta 1 subtype and those associated with the outer stripe of the medulla were of the beta 2-adrenoceptor subtype. beta 1-Adrenoceptors were concentrated over glomeruli and beta 2-adrenoceptors over the straight portion of the proximal tubule.
采用体外标记结合放射自显影技术，研究了豚鼠肾脏冰冻切片中β-肾上腺素能受体亚型的分布。（-）-[¹²⁵I]-氰基吲哚洛尔（Cyp）与肾脏切片的结合平衡和解离缓慢，对普萘洛尔和吲哚洛尔异构体具有饱和性和立体选择性。这些特性适合于与β-肾上腺素能受体结合。通过使用倍他洛尔（β₁-肾上腺素能受体）和ICI 118,551（β₂-肾上腺素能受体）以及计算机辅助曲线拟合技术来区分β-肾上腺素能受体亚型。β₁-和β₂-肾上腺素能受体均以1:2的比例存在。（-）-[¹²⁵I]-Cyp与豚鼠肾脏切片结合的³H-Ultrofilm图像显示，皮质中有局部结合斑块，髓质外带中有集中结合。皮质受体为β₁亚型，与髓质外带相关的受体为β₂-肾上腺素能受体亚型。β₁-肾上腺素能受体集中在肾小球上，β₂-肾上腺素能受体集中在近端小管的直部。
