[Effect of kainic acid on synaptic transmission in the electroreceptors (ampullae of Lorenzini) of the skate].

Superfusion of the basal membrane of the ampullae of Lorenzini of the skate Raja clavata with 10(-6)-10(-9) M kainic acid produced significant and reversible changes in background firing rate depending on its initial level. When synaptic transmission was abolished by high Mg2+ solution, succeeding superfusion with kainic acid and Mg2+ containing solution restored the background and evoked activity in the afferent fibres. It is suggested that the observed effects of kainic acid on the activity of the ampullae of Lorenzini may be explained mainly by its presynaptic action.