Inhibition of excitatory amino acid efflux contributes to protective effects of puerarin against cerebral ischemia in rats / 生物医学与环境科学(英文)
Biomedical and Environmental Sciences
;
(12): 336-342, 2007.
Article
Dans Anglais
| WPRIM
| ID: wpr-249846
ABSTRACT
<p><b>OBJECTIVE</b>To investigate whether the protective effects of puerarine (Pur) against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats.</p><p><b>METHODS</b>Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion (MCAO) for 60 min followed by 24 h reperfusion. Pur (50, 100 mg/kg, i.p.) was administered at the onset of MCAO. The infarct rate and edema rate were detected on TTC (2,3,5-triphenyltetrazolium chloride)-stained coronal sections. The extracellular levels of amino acid transmitters were monitored in striatum of rats with ischemic/reperfusion injury using in vivo microdialysis technique. Furthermore, the protective effects of Pur against glutamate-induced neurotoxicity were detected. Glutamate-induced apoptotic and necrotic cells in hippocampus were estimated by flow cytometric analysis of Annexin-V and PI labeling cells.</p><p><b>RESULTS</b>Pur (100 mg/kg) significantly decreased infarct size by 31.6% (P<0.05), reduced edema volume (P<0.05), and improved neurological functions (P<0.05) following MCAO. In these rats, the ischemia-induced extracellular levels of aspartate (Asp), glutamate (Glu), y-aminobutyric acid (GABA), and taurine (Tau) were significantly reduced in striatum of vehicle-treated animals by 54.7%, 56.7%, 75.8%, and 68.1% (P<0.01 and P<0.05). Pur reduced the peak values of Glu and Asp more obviously than those of GABA and Tau, and the rate of Glu/GABA during MCAO markedly decreased in Pur-treated MCAO rats, compared with the vehicle-treated MCAO rats. Meanwhile, apoptosis and necrosis induced by Glu in cultured hippocampal neurons were significantly reduced after Pur treatment.</p><p><b>CONCLUSION</b>Acute treatment with Pur at the onset of occlusion significantly depresses ischemia-induced efflux of amino acids, especially, excitotoxicity in the striatum, a mechanism underlying the neuroprotective effect on cellular survival.</p>
Texte intégral:
Disponible
Indice:
WPRIM (Pacifique occidental)
Sujet Principal:
Anatomopathologie
/
Pharmacologie
/
Transport biologique
/
Encéphalopathie ischémique
/
Rat Sprague-Dawley
/
Microdialyse
/
Neuroprotecteurs
/
Acides aminés excitateurs
/
Cytométrie en flux
/
Hippocampe
Limites du sujet:
Animaux
langue:
Anglais
Texte intégral:
Biomedical and Environmental Sciences
Année:
2007
Type:
Article
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