17β-Estradiol, but not estrone, increases the survival and activation of new neurons in the hippocampus in response to spatial memory in adult female rats

► Chronic estrone and 17β-estradiol did not affect acquisition of the Morris water maze. ► 17β-estradiol increased, while estrone decreased, hippocampal neurogenesis. ► 17β-estradiol increased activation of new hippocampal neurons in response to spatial memory. ► This research may provide insight into the development of hormone replacement therapies.