大鼠视网膜中不同亚型无长突细胞对N-甲基-D-天冬氨酸损伤敏感性的差异OACSTPCD

Objective:To explore the susceptibility of amacrine cell(AC)types to N-methyl-D-aspartate(NMDA)excitotoxicity in the rat retina.Methods:H-E staining was used to observe the pathological changes in retinal tissue after NMDA injury,while immunofluorescence staining was used to observe the changes in the quantity of Brn3a(the marker of retinal ganglion cell)and syntaxin(the marker of AC).In the study of the dose-effect relationship and time-effect relationship of NMDA-induced AC injury,immunofluorescence staining was used to detect the morphological and numerical changes of GAD65/67+(the marker of GABAergic AC),GlyT1+(the marker of glycinergic AC),ChAT+(the marker of cholinergic AC),TH+(the marker of dopaminergic AC),and PV+cells(the marker of AⅡ AC)in the rat retina.Propidium iodide(PI)and cleaved caspase-3 staining were employed to determine the subtypes of dead AC.Results:NMDA can damage both retinal ganglion cells and displaced ACs in the retinal ganglion cell layer(GCL),as well as ACs in the inner nuclear layer(INL).In the dose-effect relationship of AC damage induced by NMDA,all ACs significantly decreased with the increase of NMDA dose,and the cholinergic ACs in the INL and dopaminergic ACs(DAC)did not show their cell somas in 100 nmol NMDA.In the time-effect relationship of AC damage induced by NMDA,the number of GAD65/67+in INL,GlyT1+,ChAT+and TH+cells began to decrease at 6 h after injury,while the number of GAD65/67+cells in GCL,the total number of GAD65/67+cells in the retina,and PV+cells all began to decrease at 12 h after injury and continued to decrease with the progression of NMDA-induced damage.Conclusion:The GABAergic ACs and glycinergic ACs in the retina both show damage under the influence of NMDA,with cholinergic ACs in the INL and DACs being particularly sensitive to NMDA-induced damage.