Effects of Echinacoside on Histio-central Levels of Active Mass in Middle Cerebral Artery Occlusion Rats*

Key words: 
• Echinacoside /
• Norepinephrine (NE) dopamine (DA) homovanillic acid (HVA) 3,4-dihydroxyphenylethanoid acid (DOPAC) 5-hydroxyindoleacetic acid (HIAA) 5-hydroxytryptamine (5-HT) /
• Middle cerebral artery occlusion(MCAO) /
• Brain microdialysis /
• rats

Abstract: Objective To investigate the effects of echinacoside on the extracellular striatal levels of norepinephrine (NE),dopamine (DA),homovanillic acid (HVA),3,4-dihydroxyphenylethanoid acid (DOPAC),5-hydroxyindoleacetic acid (HIAA),and 5-hydroxytryptamine(5-HT) in middle cerebral artery occlusion (MCAO rats.Methods The middle cerebral artery was occluded in male Sprague-Dawley rats.Three days later microdialysis probes were placed into the right striatum of MCAO rat brains and the brains were perfused with Ringer's solution at a rate of 1.5 μL/min.Cerebral microdialysates were collected every 30 minutes from awake and freely moving rats before assaying for NE,DA,HVA,DOPAC,HIAA,and 5-HT levels by reverse phase HPLC with electrochemistry.Results Three days after MCAO,the extracellular striatal levels of NE,DA,DOPAC,HIAA,HVA,and 5-HT of the MCAO rats increased significantly (at least P＜0.05 vs.control).However,simultaneous treatment with echinacoside (30.0 or 15.0 mg/kg) attenuated these increases (at least P＜0.05 vs.non-treated model rats).Conclusion These results imply that echinacoside may protect striatal dopa minergic neurons from the injury induced by MCAO and may help prevent and treat cerebral ischemic diseases.