Bilateral enhancement of excitation via up-regulation of vesicular glutamate transporter subtype 1, not subtype 2, immunoreactivity in the unilateral hypoxic epilepsy model.
In the present study, the change of vesicular glutamate transporter (VGLUT) immunoreactivity on long-term impaired excitability in the hippocampus after recovery from unilateral hypoxic-ischemic insult was investigated in order to extend our understanding of the mechanism of epileptogenesis using unilateral hypoxic epilepsy models. Both the lesioned (submitted to ischemia) and the unlesioned hippocampi exhibited the frequent occurrence of interictal spikes and occasionally the sustained ictal discharges. However, paired-pulse inhibition was significantly reduced in the unlesioned dentate gyrus, not in the lesioned dentate gyrus. VGLUT1 immunoreactivity was significantly elevated in both hippocampi following hypoxic ischemia, although VGLUT2 immunodensity was unaltered. These findings suggest that the enhancement of VGLUT1 immunoreactivity in both hippocampi after unilateral hypoxic ischemia may contribute to the hyperexcitability, which may play an important role in the epileptogenesis (presumably accompanied by altered inhibitory transmission) after neurodegeneration.
Kim
Duk-Soo
DS
Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea.
Kwak
Sung-Eun
SE
Kim
Ji-Eun
JE
Won
Moo Ho
MH
Choi
Hui-Chul
HC
Song
Hong-Ki
HK
Kwon
Oh-Shin
OS
Kim
Yeong-In
YI
Choi
Soo-Young
SY
Kang
Tae-Cheon
TC
D000818:Animals; D015153:Blotting, Western / Q000379:methods; D004195:Disease Models, Animal; D004569:Electroencephalography / Q000379:methods; D004827:Epilepsy / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology*; D007839:Functional Laterality / Q000502:physiology*; D006624:Hippocampus / Q000378:metabolism*; D000860:Hypoxia / Q000150:complications; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015854:Up-Regulation / Q000502:physiology; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism*; D050599:Vesicular Glutamate Transport Protein 2 / Q000378:metabolism* / Q000494:pharmacology*
C493475:Slc17a6 protein, rat; C493466:Slc17a7 protein, rat; D050598:Vesicular Glutamate Transport Protein 1; D050599:Vesicular Glutamate Transport Protein 2