Abstract：OBJECTIVE: To investigate the short-term effects of flurothyl-induced neonatal recurrent seizures on γ-aminobutyric acid A receptor (GABAAR) α1 and β2 subunit expression in the rat brain, and to study the relationship between the alterations of GABAAR subunits in the developing brain and seizure-induced brain injury.METHODS: Sixty-four 7-day-old Sprague-Dawley rats were randomly divided into two groups: control and seizure. Seizures were induced by inhalant flurothyl daily for six consecutive days. The expression of GABAAR α1 and β2 subunits protein in the cerebral cortex and the hippocampus were detected by Western blot and immunohistochemistry method 1 and 7 days after recurrent seizures.RESULTS: Compared to the control, the accumulated optical density (AOD) of GABAAR α1 subunit immunoreactivity (IR) in the parietal cortex, the CA3-CA4 regions and the dentate gyrus in seizure rats increased significantly 1 day after recurrent seizures (P<0.05). The AOD of GABAAR α1 subunit IR in the parietal cortex, the CA1-CA4 regions and the dentate gyrus in seizure rats increased significantly 7 days after recurrent seizures compared with the control (P<0.05). The expression of GABAAR α1 subunit in the hippicampus and the cerebral cortex increased significantly in seizure rats compared with that in control rats 1 and 7 days after recurrent seizures. After 7 days of recurrent seizures, the AOD of GABAAR β2 subunit IR in the CA1-CA2 regions increased significantly in the seizure group compared with that in the control group (P<0.05), but the AOD of GABAAR β2 subunit IR in the thalamus decreased significantly in the seizure group compared with that in the control group (P<0.05). The expression of GABAAR β2 subunit protein in the hippocampus increased significantly in the seizure group compared with that in the control group 7 days after recurrent seizures (P<0.05). CONCLUSIONS: Recurrent neonatal seizures may result in the short-term alterations of GABAAR α1 and β2 subunits expression in the cerebral cortex and the hippocampus in rats, suggesting the alterations of GABAAR subunit expression may be related to the developing brain injury following recurrent seizures.
BO Tao,WANG Tuan-Mei,ZHU Xiao-Hua et al. Short-term effects of recurrent neonatal seizures on γ-aminobutyric acid A receptor α1 and β2 subunit expression in the rat brain[J]. CJCP, 2008, 10(3): 371-375.
