Biochem/physiol Actions

BAY 60-7550 is an orally active, potent and selective cGMP-dependent phosphodiesterase PDE2 (PDE2A) inhibitor (human/bovine PDE2 IC50 = 4.7/2.0 nM; bovine PDE1 IC50 = 108 nM, human PDE5/5A/10A/4B IC50 = 240/580/704/940/1830 nM, human PDE3B/7B/8A/9A/11A IC50 >4 µM) with little activity (IC50 >10 µM) toward acetylcholinesterase, mAO-A/B, adenosine deaminase, and many receptor subtypes tested. Bay 60-7550 effectively upregulates cGMP and cAMP level in cultured rat and murine neurons (1 nM-1 µM) exposed to guanylyl cyclase (GC) or adenylyl cyclase (AC) stimulator (1 µM Bay 41-8543 or 2 µM forskolin), respectively, as well as exhibits learning and memory-improving efficacy in rats (0.6-3 mg/kg p.o.) and mice (0.3-1 mg/kg p.o.) in vivo.