Voltage clamp study of cat spinal motoneurons during strychnine-induced seizures.

Cat spinal motoneurons were examined by the technique of somatic voltage clamp during strychnine-induced spinal seizures. No clear alteration of voltage-dependent ionic currents was required in order for typical strychnine-induced paroxysmal depolarization shifts (PDSs) to develop in contrast to results previously obtained during penicillin-induced spinal seizures. Voltage clamp of evoked and spontaneous PDSs indicates these are generated by a synchronized mixture of excitatory and inhibitory synaptic currents wih excitation predominating.