Ouabain-Induced Seizures in Rats; Relationship to Brain Monoamines

Abstract

Ouabain (5 μg) was injected into the left lateral ventricle of unanesthetized rats. Running seizures were observed in 81%, leaping seizures in 44%, and whole body flexion seizures in 31% of the animals after 5 μg of ouabain. At lower doses (0.5–2.0 μg) of ouabain, hypersensitivity to sensory stimuli was observed without seizure activity. With higher doses (10–500 μg) of ouabain, increasing severity of seizure pattern was seen. Monoamine estimations made on brain regions from animals sacrificed 15 min after injection of 5 μg of ouabain showed significant increases of serotonin in the hippocampus and decreases of norepinephrine in the midbrain region.