消癃通闭对α_1-肾上腺素受体的拮抗作用  

Characterization of the antagonistic effect on α_1- adrenoceptor of the Chinese herb medicine Xiao Long Tong Bi

作　　者：吕志珍[1] 李寅增[2] 韩启德[1] 贾金铭[3] 

机构地区：[1]北京大学第三医院血管医学研究所,北京100083 [2]北京大学药学院应用药物研究所,北京10008 [3]中国中医研究院广安门医院泌尿外科,北京10008

出　　处：《北京大学学报（医学版）》2001年第2期157-159,共3页Journal of Peking University:Health Sciences

基　　金：国家自然科学基金 (3 973 0 490 )

摘　　要：目的 :研究消癃通闭对α1 肾上腺素受体 (α adrenoceptor,α1 AR)的拮抗作用 ,为寻找有治疗作用的先导化合物提供理论依据。方法 :(1)采用放射配体结合实验 ,在犬脑细胞膜中分别加入标记后的12 5I BE2 2 5 4和 15种浓度的消癃通闭 ,测定其放射性活度。通过Hill作图求出IC50 值 ;(2 )采用离体组织收缩功能实验 ,测定消癃通闭对去甲肾上腺素介导离体大鼠前列腺收缩的拮抗作用 ,求得 pKB 值。结果 :消癃通闭对12 5I BE2 2 5 4与犬大脑皮层α1 AR的结合呈竞争性抑制作用 ,其半效抑制 (质量 )浓度IC50 为 (34 .0± 6 .0 ) g·L-1,Hill系数为 0 .7。消癃通闭可使α1 AR介导的大鼠前列腺平滑肌收缩效应曲线平行右移 ,消癃通闭在两种不同浓度时 ,其拮抗的 pKB 值分别为(37.0± 11.0 ) g·L-1和 (30 .0± 8.0 ) g·L-1。结论 :消癃通闭对α1SUMMARY Objective: To better understand the antagonistic effect of Xiao Long Tong Bi (XLTB), a Chinese herb medicine, on α 1 adrenoceptor (α 1 AR). Methods: (1) Radio ligand binding assay . Specific 125 I BE2254(2 β(4 hdroxyphenyl) ethyl amino methyl tetralone) binding was measured by incubating membrane of canine cerebral cortex with a single concentration of 125 I BE2254 in the presence of 15 concentrations of XLTB. Half effectual concentration of inhibition (IC 50 ) and Hill coefficients (n H) were determined by Hill plots. (2) Contractile responses of rat prostate strip in vitro were determined. pK B values for XLTB in competitively inhibiting NE stimulated contraction of tissues were measured by the method of Ainlakshana. Results: XLTB competitively inhibited binding of 125 I BE2254 to α 1 AR in a concentration dependent manner. IC 50 values for XLTB in canine cerebral cortex were (34.0±6.0) g·L -1 , the Hill efficiency value (0.7±0.1) was significantly decreased from unity. Contractile studies showed that XLTB competitively antagonized the NE concentration response curve with pK B values of (37.0±11.0) g·L -1 or (30.0±8.0) g·L -1 when XLTB concentration was 70 g·L -1 or 170 g·L -1 , respectively. The pK B values for XLTB in antagonizing NE induced contraction of tissues were showed to fit in well with the IC 50 values on rat prostate. Conclusion: These results suggest that XLTB appears to be a competitive antagonist for α 1 AR.

关 键 词：消癃通闭 受体 肾上腺素能Α1 拮抗作用 中药复方制剂实验研究 

分 类 号：R285.5[医药卫生—中药学]