INVESTIGATION OF THE ANTIFIBRILLATORY ACTIVITY OF SOME ANTICONVULSANT γ‐AMINOBUTYRIC ACID‐TRANSAMINASE INHIBITORS IN THE RABBIT ISOLATED HEART: COMPARISON WITH PHENYTOIN AND MEXILETINE

Open Access
Publisher Website
Google Scholar
Abstract
1 The electrical stimulation and ventricular fibrillation thresholds were measured in the Langendorff-perfused rabbit heart by application of rectangular impulses of 3 ms duration and increasing current at frequencies of 4 and 20 Hz respectively. 2 Perfusion with either phenytoin or mexiletine produced significant dose-dependent increases in both thresholds. 3 Perfusion with four anticonvulsant inhibitors of γ-aminobutyric acid (GABA)-transaminase, amino-oxyacetic acid, γ-acetylenic GABA, γ-vinyl GABA and sodium valproate, up to a concentration of 20 μg/ml, had no significant effect on either threshold. 4 The results suggest that these compounds, unlike phenytoin and mexiletine, are devoid of antifibrillatory activity.
Keywords