Fig. 6.

Effect of tadalafil on the anticonvulsant potency of valproate (a) and tiagabine (b) in the 6-Hz seizure test in mice. Tadalafil was administered 90 min, while valproate and tiagabine 15 min prior to the test. All the drugs were injected i.p. Control animals received an antiepileptic drug and 1% Tween 80 instead of tadalafil. Each experimental group consisted of 24 animals. Each ED₅₀ (+ SEM) value represented a dose of an antiepileptic drug predicted to protect 50% of mice tested against 6-Hz-induced psychomotor seizure