Effects Of Acori Graminei Rhizoma Extract On GABA Transporter 1 And Glutamate Transporter 1 Expression In Developing Rat Hippocampus After Recurrent Seizures

Objective:To investigate the expression of y-aminobutyric acid transport 1 (GAT1) and glutamate transporter 1 (GLT1) in the hippocampus of the infantile rats following recurrent seizures and the effects of extract of acori graminei rhizoma on them, and discuss the relationship between GAT1 together with GLT1 and infant epilepsy, and the anticonvulsant mechanisms of acori graminei rhizoma extract on the epilepsy rats.Methods:Seventy-two of 7-day-old(P7) Sprague-Dawley rats were randomly divided into three groups:the control group, the seizure group and the acori graminei rhizoma intervention group. Each had 24 rats that were randomly divided into three groups. Seizures in rats were induced by inhalant flurothyl daily in six consecutive days. Brain tissue was sampled at different time points (Id,3d,7d) in each group after the last seizure. The expression of GAT1 and GLT1 proteins in the brain were detected by immunohistochemistry and Western blot methods.Results:GAT1 mainly distributed in hippocampal neurons membrane of the rat brain. In the control, there were no differences among PN-13,17, and 19 day. Compared to the control, the average optical density (AOD) of GAT 1 immunoreactivity (IR) in the hippocampus of seizure rats increased significantly 1,3 and 7 day after recurrent seizures (P<0.01). The AOD of GAT1 IR in the hippocampus in the acori graminei rhizoma intervention rats decreased significantly 1, 3 and 7 days after recurrent seizures compared with the seizure rats (p<0.01). Acori graminei rhizoma intervention rats had no difference to the control group. In the control, the AOD of GLT1 IR also had no differences among PN-13d,17d, and 19d. Comparing with the seizure rats, the AOD of GLT1 IR in the hippocampus in the seizure rats increased significantly on PN-13d and PN-19d (P<0.01). On PN-15d there were no significantly differences between the seizure rats and control rats. The expression of GLT1 in acori graminei rhizoma intervention group was higher than the control group and the seizure group (P<0.01). Western blot method was used in comparing the protein expression of GAT1 and GLT1 in the hippocampus among the three groups. In the control group, the GAT1 ptotein on PN-19d was lower than the PN-13d and PN-15d. The expression of GAT1 protein increased significantly in the seizure rats compared with that in control group and graminei rhizoma intervention group on PN-13d, PN-15d, ARS-7d (P<0.01). The expression of GAT1 protein graminei rhizoma intervention group was higher than the cantrol group on PN-15d, PN-19d (P<0.01), but had no difference on PN-13d. In the control, the expression of GLT1 protein had no differences among PN-13d,17d, and 19d. The expression of GLT1 protein increased significantly in the seizure rats compared with that in control group on PN-13d, PN-15d, ARS-7d (P<0.01). And in the graminei rhizoma intervention group, the expression of GLT1 was higher than the seizure group and control group (P<0.01).Conclusions:â‘ ecurrent seizures in neonatal rats may caused the abnormal expression of GAT1 and GLTl in hippocampus area, the imbalance of GAT1 and GLT1 may be involved in the pathology of developing brain injury.â‘¡Acori graminei rhizoma extract can make the imbalance expression of GAT1 and GLT1 caused by recurrent seizures in neonatal rats hippocampus area to balance.