Fig. 1.

Estradiol replacement protocol. Two weeks after gonadectomy, female rats received a series of subcutaneous injections of estradiol benzoate (EB) and 17β-estradiol (E₂) to simulate temporal changes in physiologically relevant circulating levels of estradiol during the estrous cycle. Animals were euthanized during the replacement protocol equivalent of the proestrus phase. Protocol was originally developed and validated by Scharfman and colleagues (Scharfman et al. 2007). P, postnatal day.