Regulation Of GS And GLAST In The Retinal Müller Cells Of Mice By Hypoxia

Objective:To study the regulation of glutamine synthetase(GS), GLAST by hypoxia in the retinal M(u|¨)ller cells of mice.Methods:(1) Retinal M(u|¨)ller cells of mouse at postnatal day 7-10 were cultured by tissue inoculation.(2) Cultured retinal M(u|¨)ller cells were divided into two groups:â‘ hypoxia group:cultured retinal M(u|¨)ller cells were maintained with CoCl₂ for 6h,12h,18h,24h,48h,72h respectively in vitro;â‘¡Control group:cultured retinal M(u|¨)ller cells without CoCl₂.(3) The expression of GS and GLAST protein in the retinal M(u|¨)ller cells was detected with immunocytochemical staining.(4) The expression of GS mRNA and GLAST mRNA in the retinal M(u|¨)ller cells was semi-quantified by RT-PCR.Results:(1) Immunocytochemical staining indicated that GS and GLAST protein located in the cytoplasm and membrane of retinal M(u|¨)ller cells. The expression of GS and GLAST protein was up-regulated as the increase of the anoxic times.The hypoxia for 24h caused the maximal expression of GS and GLAST protein which was higher than that in the control group(P＜0.05).However with the time extend,the expression of GS and GLAST protein decreased,which got to the minimal expression in 72h.(2) The expression of GS and GLAST mRNA in retinal M(u|¨)ller cells was up-regulated as the increase of the anoxic times.The hypoxia for 24h caused the maximal expression of GS and GLAST mRNA,the grey scales of GS and GLAST mRNA by scanning were 0.7967±0.1986,0.7333±0.059 respectively,which is higher than that in the control group(P＜0.05).However with the time extend,the expression of GS and GLAST mRNA decreased,which got to the minimal expression in 72h.Conclusion:Hypoxia can upregulate the expression of GS,GLAST mRNA and protein in retinal M(u|¨)ller cells of mice,which may enhance the activity of GS and GLAST...