[Expression of phosphorylated NMDA receptor 1 in the cerebral cortex after NMDA microinjection in vivo].
OBJECTIVE
The activation of N-methyl-D-aspartate(NMDA) receptors plays critical roles in the pathogenesis of diseases of the brain. This study aimed to examine the expression of phosphor-NR1 S897 in the cerebral cortex after NMDA microinjection in vivo.


METHODS
Forty seven-day-old Sprague-Dawley rats were randomly assigned into normal control and NMDA injection groups. The rats from the NMDA injection group were injected with 10 mmol of NMDA and were sacrificed 1 hr after injection. 2, 3, 5-triphenyltetrazolium chloride (TTC) and fluorescent immunohistochemical stainings were conducted and the fluorescence intensity OD value between the two groups was compared.


RESULTS
TTC staining from the two groups was normal. Expression of phosphor-NR1 S897 in the cerebral cortex of the ipsilateral hemisphere to injection in the NMDA injection group decreased significantly compared with the normal control group, with OD values of 0.366 +/- 0.087 vs 1.364 +/- 0.268 (P < 0.01).


CONCLUSIONS
NMDA microinjection, as a hypoxia-ischemia (HI) insult, significantly decreased the expression of phosphor-NR1 S897. This indicates the importance of the "HI-NMDA-phospho-NR1 S897 dephosphorylation-cell damage" pathway in HI brain damage.
Hei
Ming-Yan
MY
Division of Neonatology, Third Xiangya Hospital of Central South University, Changsha 410013, China. heiming_yan@yahoo.com.cn
Xiao
Mi-Li
ML
Kuang
Shou-Jin
SJ
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism; D008297:Male; D008845:Microinjections; D016202:N-Methylaspartate / Q000008:administration & dosage*; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis / Q000187:drug effects*
C409466:NR1 NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate