The Study Of NR1Functional Subunits Of NMDA Receptor In Schizophrenia Hippocampal Neurogenesis Regulation

Objective Through the in vivo experiment, to investigate the expression changes of NR1,BrdU(5-Bromo-2-deoxyUridine) and Ki67(Nuclear Associated Antigen) in the hippocampaldentate gyrus (DG) of Schizophrenia (SP) model mice that subject to intracerebroventricularinjection of NMDA (N-metthy-D-aspartic acid) receptor agonist. Through the in vitroexperiment, to Primitive culture of hippocampal neural stem cells (NSCs), using of MTSand the Annexin V-FITC/PI test the influence of MK-801(dizocilpine) and NMDA forhippocampal neural stem cell proliferation. Immune cell method detect the expression of NR1and BrdU situation. Through this experiment, to discuss the possible mechanism of action, toexpound NR1in the pathogenesis of schizophrenia may be potential value, and in order toprovide experimental basis for further research.Methods1. Immunohistochemical staining was used to observe the expression of NR1,BrdU and Ki67in the DG granular layer under confocal laser scaning microscope.2Primitiveculture and identification.3The MTS method fumble MK-801and NMDA effect time andconcentration of hippocampus NSCs.4MTS test MK-801and NMDA affect hippocampalNSCs proliferation.5Flow cytometry instrument to detect NMDA and MK-801on theinfluence of NSCs apoptosis.6Cell immunofluorescence method to detect the expression ofNR1and BrdU situation.Results1To investigate the expression changes of NR1, BrdU and Ki67in thehippocampal DG:1) The number of NR1positive cells in NMDA group and blank group is20.450%and33.79%(P<0.05) lower than that of SP group, and21.12%and34.48%(P<0.05) lower than that of saline group respectively; the NMDA group compared with the blankcontrol group had no significant difference (P>0.05).2) BrdU and Ki67positive cells wasbroadly in line with a change trend. The number of BrdU positive cells in NMDA group andblank group is34.62%and35.85%more than that of SP group (P<0.05), and32.69%and33.96%more than that of saline group (P<0.05) respectively; the NMDA group comparedwith the blank control group had no significant difference (P>0.05). The number of Ki67positive cells in NMDA group is64.41%and41.85%more than that of SP group and NSgroup (P<0.001); NMDA group and the blank group has statistical significance, the NMDAgroup compared with the blank control group fell by11.09%（P<0.001）.2The MTS method fumble MK-801and NMDA effect time and concentration ofhippocampus NSCs: the final concentrations of MK-801on NSCs is200μM, and action time is24h. The final concentrations of NMDA on NSCs is100μM and action time of2h.3MTS test MK-801and NMDA affect hippocampal NSCs proliferation: Cell survivalrate of the blank group is100%by default, OD value of the blank group is more than that ofthe other groups, there are significant（P<0.01）. OD value of the M group is lower than that ofthe NMDA and the M+N groups，the Cell survival rate in M group is43.83%lower than that ofN group (P<0.001) and42.25%lower than that of M+N group (P<0.01); the NMDA groupcompared with the M+N group had no significant difference (P>0.05).4Flow cytometry instrument to detect NMDA and MK-801on the influence of NSCsapoptosis:1) The survival rate: M+N group and Control group, MK-801set of NMDA groupwere higher, and no statistical difference between the two groups(P>0.05).2) Total rate ofapoptosis: the total apoptosis rate of the M+N group and the blank group is lower than that ofthe NMDA group and the MK-801group, and the M+N group is26.89%and19.79%(P<0.05)lower than that of the MK-801group and the NMDA group; the M+N group compared withthe blank group had no significant difference (P>0.05).3) The early apoptosis rate: the earlyapoptosis rate of the M+N group and the blank group is lower than that of the NMDA group and the MK-801group, and the M+N group is55.68%and50.45%(P<0.001) lower than thatof the MK-801group and the NMDA group; the M+N group compared with the blankgroup had no significant difference (P>0.05).4) The late apoptosis rate: the late apoptosis rateof the M+N group and the blank group is more than that of the NMDA group and the MK-801group, and the M+N group is41.21%and51.07%(P<0.001) lower than that of the MK-801group and the NMDA group; the M+N group compared with the blank group had nosignificant difference (P>0.05).5Cell immunofluorescence method to detect the expression of NR1and BrdU situation:Each group of NR1and BrdU average optical density value had no statistical difference (P>0.05).Conclusions After intracerebroventricular injection of NMDA receptor agonist in SPmodel mice with negative symptoms, the number of NR1positive cells in DG granular layerreduced, while the proliferation ability of nerve cells increased. MK-801and NMDA has theInhibit the proliferation of the NSCs cells, and was positively correlated with drug effect timeand concentration. As the extension of drug effect time and the increase of drug concentration,MK-801and NMDA inhibition of cell proliferation was gradually strengthened. The finalconcentrations of MK-801on NSCs is200μM, and action time is24h. The final concentrationsof NMDA on NSCs is100μM and action time of2h. NMDA can inhibit the MK-801producedby the nerve cell toxicity, has the nerve protective effect.