Tolszczuk M, Pelletier G
MRC Group in Molecular Endocrinology, Le Centre Hospitalier de l'Université Laval, Ste-Foy, Québec, Canada.
J Histochem Cytochem. 1988 Dec;36(12):1475-9. doi: 10.1177/36.12.2848069.
The inhibitory effects of catecholamines on uterine smooth muscle are known to be mediated through beta-adrenergic receptors. To investigate further the distribution of these receptors in the rat uterus, we utilized in vitro autoradiography using [125I]-cyanopindolol [CYP], a specific beta-receptor ligand that has equal activity for both beta 1- and beta 2-receptor subtypes. The specificity of the labeling and the characterization of receptor subtypes in different cell types were achieved by displacement of radioligand with increasing concentrations of zinterol, a beta-adrenergic agonist with preferential affinity for the beta 2-adrenoreceptor subtype, and practolol, a beta-adrenergic antagonist that binds preferentially to the beta 1-subtype. Quantitative estimation of ligand binding was performed by densitometry. It was shown that the vast majority of beta-adrenoreceptors were of the beta 2-subtype and were found in high concentration not only in the myometrium but also in the endometrial and serosal epithelia. Specific labeling was also observed in glandular elements. These results suggest that beta-adrenoreceptors might be involved in different functions in the uterus.
已知儿茶酚胺对子宫平滑肌的抑制作用是通过β-肾上腺素能受体介导的。为了进一步研究这些受体在大鼠子宫中的分布，我们使用了[125I]-氰基吲哚洛尔[CYP]进行体外放射自显影，[125I]-氰基吲哚洛尔是一种特异性β受体配体，对β1和β2受体亚型具有同等活性。通过用浓度递增的齐特罗（一种对β2-肾上腺素能受体亚型具有优先亲和力的β-肾上腺素能激动剂）和心得宁（一种优先与β1亚型结合的β-肾上腺素能拮抗剂）取代放射性配体，实现了标记的特异性和不同细胞类型中受体亚型的表征。通过光密度测定法对配体结合进行定量估计。结果表明，绝大多数β-肾上腺素能受体是β2亚型，不仅在子宫肌层中浓度很高，而且在子宫内膜和浆膜上皮中也有高浓度分布。在腺体成分中也观察到特异性标记。这些结果表明，β-肾上腺素能受体可能参与子宫的不同功能。
