Effects of short-term hormonal replacement on learning and on basal forebrain ChAT and TrkA content in ovariectomized rats

► E2 had a positive effect on cognition in an autoshaping learning task. ► P4 blocked E2 effects on cognition in an autoshaping learning task. ► ChAT and TrkA content in basal forebrain was sensitive to hormonal influence. ► The behavioral results correlated with basal forebrain TrkA.