滋补肝肾、通络解毒中药对异动症大鼠行为学及纹状体多巴胺D2受体活性的影响

目的：观察滋补肝肾、通络解毒中药对异动症大鼠行为学和多巴胺D2受体活性的影响。方法：采用6-羟基多巴胺（6-hydroxydopamine,6-OHDA）注射于大鼠脑右侧黑质造成偏侧帕金森病（Parkinson＇s disease,PD）模型,进一步对PD大鼠予以左旋多巴/苄丝肼制作异动症（levodopa-induced dyskinesias,LID）模型。实验设立正常对照组、模型组、中药干预组、中止给药对照组和中止给药＋中药干预组,观察中药对LID大鼠异常不自主运动（abnormal involuntary movement,AIM）评分的影响,测定大鼠纹状体多巴胺D2受体的最大结合容量（maximum binding capacity,Bmax）和平衡解离常数（equilibrium dissociation constant,KD）,来评价中药对LID大鼠多巴胺D2受体亲和力的影响。结果：与模型组和中止给药对照组比较,中药干预组可明显减少异动症大鼠的AIM积分（P〈0.01）;纹状体多巴胺D2受体亲和力检查示,中药可使Bmax显著上调（P〈0.05,P〈0.01）,KD值下降（P〈0.01）,多巴胺D2受体亲和力显著提高。结论：滋补肝肾、通络解毒中药可以有效缓解异动症症状,明显改善纹状体多巴胺D2受体活性。

Effects of traditional Chinese herbal medicine on the neurobehavioral manifestations and the activity of dopamine D2 receptor in corpora striatum of rats with levodopa-induced dyskinesias

OBJECTIVE: To explore the effect of traditional Chinese herbal medicine (TCM) for nourishing liver and kidney, clearing meridians and removing toxic substances, on the neurobehavioral manifestations and the activity of the dopamine D2 receptor in rat with levodopa-induced dyskinesias (LID). METHODS: The rat model of Parkinson's disease (PD) was established by injecting 6-hydroxydopamine (6-OHDA) into right substantia nigra of brain, then, the model of LID in rat was produced by injecting levodopa (LD) and benserazide for 4 weeks. The rats were divided into normal control group, 4-week LD treated group, 4-week LD plus TCM treated group, 8-week LD treated group, and 8-week LD plus TCM treated group, and the effect of the TCM on neurobehavioral manifestations was observed. The radioligand binding assay (RLBA) and Scatchard drawing were used to measure the maximal binding capacity of receptor (Bmax) and equilibrium dissociation constant (KD) of the dopamine D2 receptor in corpora striatum. RESULTS: Compared with the 4-week LD treated group and 8-week LD treated group, TCM could decrease abnormal involuntary movement scores of the rats with LID; the RLBA revealed that the dopamine D2 receptor Bmax significantly increased (P<0.05, P<0.01) and the KD significantly decreased (P<0.05). CONCLUSION: TCM can improve the activity of the dopamine D2 receptor and relieve the symptoms of LID.