Feline generalized epilepsy induced by tranexamic acid (AMCA).

Epileptic activities induced by topical application of tranexamic acid (AMCA) and penicillin to the cortex of 12 cats in acute experiments were compared. Both substances when diffusely applied on a wide cortical area of both hemispheres at very low concentration produced an EEG pattern consisting of spike-wave bursts similar to the electrographic manifestations seen in feline generalized epilepsy induced by large parenteral doses of sodium penicillin. These epileptic bursts could be triggered by repetitive stimulation of nucleus centralis medialis. Increased concentrations of both AMCA and penicillin led to the appearance of bilaterally synchronous spikes and poly-spikes which were not further excited by NCM stimulation. Two factors seem to play an important role in eliciting spike-wave bursts in both models: (1) the area of the cortex exposed to the epileptogenic agent and (2) the concentration of the epileptogenic agent used. The similar effects observed in 5 chronic animals either by intravenous injection of high doses of AMCA or by intramuscular injection of sodium penicillin confirm the results obtained in acute experiments and suggest a new way of inducing feline generalized epilepsy.