GRIN1 and Alzheimer disease: As outlined in Results, the different GluN1/α7 ratios in the AD and non-AD pull-downs can not be explained by the different expression levels of α7 and GluN1 in the two tissues, and this is further evident from the different GluN1/α7 ratios in pull-down samples from adult 3xTg-AD and WT mouse cortical homogenates characterized by comparable expression levels of the two subunits (Figs 2 and 3).