Tacrine (12.5-37.5 nM) inhibits venom acetylcholinesterase as well as human serum butyrylcholinesterase in a concentration-dependent manner. Tacrine reduces the neurotoxicity induced by the activation of the NMDARs in murine cortical neuronal cultures with an IC 50 of ~500 μM. Tacrine inhibits the NMDAR responses in a concentration-dependent manner with an IC 50 of ~190 μM at -60 mV.
Tacrine (20-40 μmol/kg; s.c.) disrupts retention of learning in 17- and 30-day old mice in passive avoidance, and while the low dose of tacrine treatment (5 μmol/kg; s.c.) improves retention in 17-day old mice. Tacrine (0.1-0.4 mg/mL; i.p. for 7 d) inhibits the expression of AChE, but does not significantly improve the protection of the retina function and morphology in mice.