[Dynamic changes of striatal monoamines with in vivo microdialysis in ischemic rats].
Using intracerebral microdialysis, high performance liquid chromatography and electrochemical detection (HPLC-ECD), we determined the contents of extracellular dopamine (DA), serotonin (5-HT) and their metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid(HVA) and 5-hydroxy-indole acetic acid (5-HIAA) in the striatum of rats after the occlusion of middle cerebral artery (MCAO). The dialysis tube was implanted stereotaxically in the lateral 2/3 of the striatum. No significant effects of stressors were noted on the concentration of neurotransmitter mentioned above. A step rise of extracellular DA and 5-HT accompanied by significant reduction of DOPAC, HVA and 5-HIAA was found 10 minutes after MCAO. From then on, the enhanced concentrations of DA and 5-HT decreased gradually. At 3 hours after MCAO, however, DA and 5-HT were still high with respect to the basal levels. Their metabolites were kept at low levels at 3 hours of MCAO. In conclusion, the massive leakage of DA and its over production of oxygen free radicals are important for the development of ischemic cell damage in the striatum.
Wei
Z Y
ZY
Department of Neurosurgery, Tianjin Huanhu Hospital.
D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism*; D003956:Dialysis; D004298:Dopamine / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism
D015306:Biogenic Monoamines; D012701:Serotonin; D004298:Dopamine