SLC32A1 and Alzheimer disease: To address whether these structural changes would lead to the alterations in synaptic strength of the MS-DG connections, we injected AAV5-DIO-YFP-ChR2 into the MS of 14 months old Vgat-WT or Vgat-AD mice and recorded sIPSCs in GCs upon optogenetic activation of MS-DG projections (similar to Fig. 5A).