Effect Of Taurine On AQP4/Taurine Transporter Gene Expression In The Rats With Traumatic Brain Injury

Objective To investigate the changes of the brain water content and AQP4\taurine transporter gene expression in brain tissue after the treatment of taurine in rats with traumatic brain injury (TBI).Methods 84 male SD rats were randomly divided into 7 groups:sham group (Sham group), traumatic brain injury group (TBI group), taurine treatment group (Tau group), taurine prevention group (Pre-Tau group),β-alanine group (β-Ala group), vitamin C group (Vc group), folic acid group (Fa group). Each group had 12 rats. TBI models of the latter six groups were performed by lateral fluid percussion. The rats were administered drugs (drug dose:200mg/kg) intravenously immediately after TBI. Sham group and TBI group were given isotonic saline. The histopathological changes of brain tissue were observed by HE stain. Brain water content was measured by using the dry-wet weight assay, the expression of AQP4\taurine transporter (Taurine Transporter. TAUT) gene was analyzed by fluorescence quantitative RT-PCR After TBI 24 hours.Results1. Morphology:TBI rats presented typical brain edema which the neuron swelling, cell losing, karyopyknosis and inflammatory cells infiltrated at he edge of necrosis at 24h after TBI. However, compared with TBI group, morphology of the cells of Tau group, Vc group, Fa group and Pre-Tau group had not obviously changed. The change ofβ-Ala group was the same as TBI group.2. Brain water content:The brain water content of TBI group andβ-Ala group were significantly increased than those of Sham group. The brain water content of Tau group, Vc group and Fa group were decreased obviously, which were not significantly different to those of Sham group. The brain water content of Pre-Tau group was significantly lower than that of Sham group.3. Gene expression:The expression of AQP-4 mRNA of TBI group was significantly higher than that of Sham group. The expression of AQP-4 mRNA of Tau group, Vc group, Fa group, Pre-Tau group and B-Ala group was significantly decreased, which had no significant statistical difference with Sham group. The expression of TAUT mRNA of Fa group was significantly higher than that of Sham group. The expression of TAUT mRNA of TBI group, Tau group, Vc group, Pre-Tau group and B-Ala groups had no difference.Conclusion1. Tau, Vc, Fa, and taurine preventive treatment could significantly reduce brain edema and down-regulate the expression of AQP -4 gene.2. Because Tau, Vc, Fa, and taurine preventive treatment could significantly reduce the expression of AQP -4 gene, they have the therapeutic effect on brain edema after traumatic brain injury.3. Tau and Vc have no effect on TAUT regulation after TBI, and their effect on the brain water content is not by adjusting the TAUT to achieve.