GPER1 and Anxiety: To further explore the role of GPER in the modulation of anxiety, we conducted EPM and open field tests to observe the effects of ovariectomy (OVX) and systemically administered E2 (endogenous GPER agonist, 10 μg/kg, s.c.)or G-1 (synthetic GPER agonist, 10 μg/kg, s.c.)on anxiety-like behaviors in 10-week-old female rats.