川芎嗪对VEGF受体与其放射性配体结合的抑制

目的探讨川芎嗪对VEGF受体与其放射性配体结合的影响。方法采用血清药理学方法,分别制备川芎嗪大剂量、小剂量、阳性对照组鱼精蛋白、生理盐水各组含药血清,采用反相高效液相色谱法测定川芎嗪含药血清中药物浓度。将各组血清作用于人脐静脉内皮细胞ECV304,采用放射配体受体结合分析法(RBA)观察川芎嗪对VEGF受体最大结合容量(Bmax)和解离常数(Kd值)的影响。结果川芎嗪大剂量组Kd=343.30±36.64pmol·L-1,Bmax=46.26±5.85fmol/2×105cells,与生理盐水组相比Kd增大(P<0.05),Bmax减小(P<0.05)。川芎嗪小剂量组与生理盐水组相比Kd有增大趋势、Bmax有减小趋势,但差异无显著性。阳性对照组Kd=179.07±25.65pmol·L-1,受体最大结合容量Bmax=38.65±9.83fmol/2×105cells,与生理盐水组相比Kd差异无显著性(P>0.05),Bmax减小(P<0.05)。结论在川芎嗪作用下VEGF受体与125IVEGF结合的亲和力下降,VEGF受体数目下降,川芎嗪抑制VEGF受体与125IVEGF结合。川芎嗪含药血清(143.0mg·kg-1组)抑制VEGF受体与125IVEGF结合。

Tetramethylpyrazine inhibition on binding of radiolabeled ligand to VEGFR

Aim To study the effect of tetramethylpyrazine(TMP) on binding of 125I-VEGF to VEGF receptor. Methods The mice sera were collected after peritoneal injection with big-dose TMP,low-dose TMP,protamine and NS. A reversed-phase high performance liquid chromatography(RP-HPLC) method was used to determine the TMP in mice serum. The culture medium of ECV304 was treated with the mice sera in different groups. Radioligand binding assay(RBA) of receptor and Scatchard pot were performed to observe the changes of the maximum binding capacity(B_ max) and dissociation constant(K_d).Results The sera of big-dose TMP inhibited 125I-VEGF binding to its receptor, K_d=343.30±36.64 pmol·L-1,B_ max=46.26±5.85 fmol/2×10~5 cells(P<0.05). The low-dose TMP did not affect 125I-VEGF binding to VEGF. Protamine inhibited 125I-VEGF binding to VEGF, K_d had no change(P>0.05),but B_ max decreased(P<0.05). Conclusion TMP decreased the expression and binding power of VEGFR. The sera of big-dose TMP inhibited 125I-VEGF binding to VEGF.