Effects Of The General Cistanosides On The Striatal Extracellular Levels Of Monoamines Neurotransmitters In Rat Model Of Parkinson's Disease

Aim:To study the experimental methodology based on cerebral microdialysis(BMD)and high performance liquid chromatography with electrochemicaldetection(HPLC-ECD), make the acute rat model of Parkinson's diseases(PD)induced by 6-hydroxydopamine(6-OHDA), examine the effects of the generalcistanosides(GCs) on the striatal extracellular levels of monoamines neurotransmittersin rat model of PD and find the possible mechanisms of the neuroprotective actionproduced by GCs.Methods: The whole experiment was separated into three steps. At the first step, 5rats were used to determine the experimental method. They were implanted thecannulas into the right striatums of rats according to the followingcoordinates:A:+0.2mm,L:+3mm,V:3.5mm and the microdialysates were collected andmeasured by HPLC-ECD 24h later. At the second step, 10 rats were divided intocontrol and model groups randomly. 4μl (12μg/4μd) 6-OHDA or 0.9% saline werethen injected into the right striatums of rats respectively according to the coordinatesmentioned before. In the 7th day after injection, cerebral microdialysis was performedand the dialysates were determined in order to know whether or not the model of PDwas successful. At the third step, 25 rats were randomly divided into control, model,GCs low dose, GCs high dose and medopar groups. After 6-OHDA 12μg/4μl wasinjected (except the control group which was given equal volume of 0.9% saline),drugs or vehicle were administered through introperitoneal injection, one time a day,for seven consecutive days. Then the new striatal extracellular fluids were gained bycerebral microdialysis and the striatal extracellular levels of DA, DOPAC, and HVAwere measured by the same method.Results: The results showed that the experimental methodology was scientific, thePD model was relatively successful, and the striatal extracellular levels of DA,DOPAC and HVA in GCs low dose, GCs high dose and medopar groups were higherthan that in model group obviously(P＜0.05, P＜0.01 or P＜0.001 vs model group).Conclusion: Our findings demonstrated that the methods we used to determinemonoamines neurotransmitters and build the rat model of PD were reliable andrelatively successful. GCs could prevent the striatal extracellular levels of DA,DOPAC and HVA from diminution in the awake, freely moving PD model ratsinduced by 6-OHDA.