Effects of protein kinase A and G inhibitors on hippocampal cholinergic markers expressions in rolipram- and sildenafil-induced spatial memory improvement

►Sildenafil at 3 mg/kg as well as rolipram at 0.03 mg/kg increased spatial memory. ►H89 as a PKA inhibitor attenuated rolipram-induced memory improvement. ►KT5823 as a PKG inhibitor decreased memory improvement induced by sildenafil. ►Training process increased the ChAT and VAChT expression in the hippocampus. ►None of the treatments had an effect on hippocampal ChAT and VAChT levels.