Compared efficacy of quinidine, GABA and N-trimethyl GABA upon a model of ventricular automaticity

The effects of GABA, its quaternary derivative N-trimethyl GABA and quinidine have been studied in a model of ventricular automaticity induced in the isolated right ventricle of the rat. GABA shows low anti-automatic activity. N-trimethyl GABA and quinidine were, however, very effective drugs in the reduction of the automatic ventricular rate. The efficacy of the latter two drugs at 5 X 10(-5) M was not significantly different. We conclude that N-trimethyl GABA has some anti-automatic activity in this experimental model, similar to a classic antidysrhythmic drug such as quinidine, that would warrant further research.