GRIA1 and Alzheimer disease: The protein levels of postsynaptic density protein-95 (PSD-95), AMPA glutamate receptor subunit GluR1, and synaptophysin (the major synaptic vesicle protein p38 located in presynaptic terminal buttons) were measured in area CA1 of 3xTg-AD and Ntg mice for both the running and sedentary groups via Western blot assays (Fig. 4).