【摘要】 目的目前对何首乌延缓衰老的机理还不清楚，本研究探讨何首乌对大鼠中枢神经系统纹状体多巴胺受体Ｄ２的影响。方法使用受体Ｄ２拮抗剂３Ｈ－螺环哌啶酮及受体放射配体结合分析法测定大鼠纹状体匀浆中Ｄ２受体结合位点（Ｂｍａｘ）和平衡离解常数（Ｋｄ）值，观察青年、老年大鼠服用何首乌２个月前后上述参数的变化。结果未用药组衰老时Ｄ２受体数量显著下降，老年组Ｂｍａｘ值（１８４±２０ｆｍｏｌ／ｍｇ蛋白）为青年组（３１９±３１ｆｍｏｌ／ｍｇ蛋白）的５７．７％；青年大鼠用药后Ｂｍａｘ值较用药前有增加趋势，但差异无显著性；老年大鼠用药后Ｂｍａｘ值显著增加（为２８２±３０ｆｍｏｌ／ｍｇ蛋白）。年龄及何首乌对Ｋｄ值无影响。结论何首乌能改善老年大鼠中枢多巴胺能神经系统的功能。更多还原

【Abstract】 Objective The mechanism of delaying aging by Polygonum maltiflorum Thunb (PmT)is not clear at present. In this study the influences of PmT on rat striatal dopaminergic D2 receptor were observed. Methods Using D2 receptor antagonist 3H-Spiperone and radioligand binding assay of receptor, the Bmax and Kd values of D2 receptor in rat striatal homogenates were measured. The changes of the values were observed before and after using PmT. Results The receptor density Bmax decreased significantly with aging in no PmT group, the Bmax of old group (184±20 fmol/mg protein) was 57. 7% of that of young group (319±31 fmol/mg protein). The Bmax of young group tended to increase after using PmT, but the difference was not significant; the Bmax of old group increased significantly after using PmT (from 184±20 fmol/mg protein to 282±31 fmol/mg protein).Age and PmT had no influence on the apparent dissociation constant Kd of D2 receptor. Conclusions These results suggest that PmT can improve function of centrol dopaminergic nerve system in aging.更多还原