To investigate whether CaSR also mediates the synaptic impairment in the AD mouse model, the expression levels of the presynaptic marker synaptotagmine-1 and postsynaptic mark PSD 95 were measured in the hippocampus of the mice which were microinjected with Aβ1–42 (4 μmol/kg) and/or (0.08 or 0.16 μmol/kg) NPS 2143 (Figures 6A,C). The gene discussed is SYT1; the disease is Alzheimer disease.