通过放射性配体结合研究鉴定小鼠子宫肌层中的β-肾上腺素能受体。

Identification of beta-adrenoceptors in mouse myometrium by radioligand binding study.

作者信息

Chen G F, Lu Y Q, Yang Z C

机构信息

Department of Pharmacology, School of Basic Medical Sciences, Shanghai Medical University, China.

出版信息

Zhongguo Yao Li Xue Bao. 1994 Jul;15(4):336-8.

PMID:7801776

Abstract

The binding of radioligand to cell membrane prepared from mouse myometrium was used to identify the characteristics of beta-adrenoceptors. Uteri were taken from mature mice (Kunming Strain) weighing 40 +/- 5 g pretreated with estradiol benzoate 1 mg.kg-1.d-1 ip for 2 d. The binding of [3H]dihydroalprenolol ([3H]DHA) to uterine membrane was saturable, having a Bmax of 378 fmol/mg protein and a KD of 3.1 nmol.L-1. The slope of Hill plot (nH = 1.03) indicated the absence of cooperative interactions. IC50 and K1 values of l-norepinephrine (NE), dl-propranol (Pro), d-timolol (d-Tim), and l-Tim competed for the [3H]DHA binding sites were 171 +/- 10, 10.3 +/- 4.3, 6.5 +/- 2.1, 0.40 +/- 0.23 nmol.L-1 and 113 +/- 6, 6.3 +/- 2.8, 4.0 +/- 1.3, 0.25 +/- 0.14 nmol.L-1, respectively. These 4 agents competed for the [3H]DHA binding sites in an order of potency: l-Tim > d-Tim > Pro > NE. Atenolol (Ate) did not compete for [3H]DHA binding sites. The results suggested that these binding sites for [3H]DHA in mouse myometrium appeared to be beta 2-adrenoceptor.

摘要

利用放射性配体与从小鼠子宫肌层制备的细胞膜的结合来鉴定β-肾上腺素能受体的特性。子宫取自体重40±5 g的成熟小鼠（昆明种），这些小鼠腹腔注射1 mg·kg⁻¹·d⁻¹苯甲酸雌二醇预处理2天。[³H]二氢阿普洛尔（[³H]DHA）与子宫膜的结合具有饱和性，Bmax为378 fmol/mg蛋白，KD为3.1 nmol·L⁻¹。希尔图的斜率（nH = 1.03）表明不存在协同相互作用。去甲肾上腺素（NE）、普萘洛尔（Pro）、噻吗洛尔（d-Tim）和左旋噻吗洛尔（l-Tim）竞争[³H]DHA结合位点的IC50和K1值分别为171±10、10.3±4.3、6.5±2.1、0.40±0.23 nmol·L⁻¹和113±6、6.3±2.8、4.0±1.3、0.25±0.14 nmol·L⁻¹。这4种药物竞争[³H]DHA结合位点的效力顺序为：l-Tim＞d-Tim＞Pro＞NE。阿替洛尔（Ate）不竞争[³H]DHA结合位点。结果表明，小鼠子宫肌层中[³H]DHA的这些结合位点似乎是β₂-肾上腺素能受体。