【摘要】 用放射配体结合法鉴定小鼠子宫平滑肌β肾上腺素受体,结果显示l-去甲肾上腺（NE）,dl-普萘洛尔（Pro）,d-噻吗洛尔（d-Tim）,l-Tim的IC₅₀依次为171±10,10.3±4.3,6.5±2.1·0.40±0.23 nmol·L^-1;K₁依次为113±6,6.3±2.8,4.0±1.3,0.25±0.14nmol·L^-1,亲合力顺序为l-Tim>d-Tim>dl-Pro>l-NE,阿替洛尔不能抑制[³H]二氢阿普丙洛尔的结合,提示小鼠子宫平滑肌具有β₂肾上腺素受体。更多还原

【Abstract】 The binding of radioligand to cell membrane prepared from mouse myo-metrium was used to identify the characteristics of β-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 Hdihydroalprenolol ([3H]DHA) to uterine inembrane was saturable, having a Bmax of 378 tmol/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 W-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 β2-adrenoceptor.更多还原