Estrogen induces structural changes at synapses of the hippocampus, an area of the brain important for learning and memory. Exposure to estradiol stimulates glutamatergic synaptogenesis among cultured hippocampal neurons, indicated by increased cluster size and density of co-localized presynaptic vesicular glutamate transporter protein (vGlut1) and postsynaptic NMDA receptor (NR1 subunit). These findings carry important implications for the role of estradiol in learning and memory, and further demonstrate the impact that this pleiotropic hormone can exert in neuroregeneration.