Sodium pentobarbital abolishes bursting spontaneous activity of dorsal cochlear nucleus in rat brain slices

There is evidence that pentobarbital, a commonly used anesthetic, can affect neuronal activity, but its effects on particular neurons of the dorsal cochlear nucleus (DCN) are not well known. Bursting (complex spiking) spontaneous activity has been observed in the DCN in brain slice preparations and in recordings from unanesthetized decerebrate animals, but seldom in experiments with anesthetized animals. This study investigated the effects of pentobarbital on spontaneous activity in the DCN in brain slices. Most extracellularly recorded bursting neurons decreased firing rates and reversibly changed their firing to simple spiking with irregular intervals during pentobarbital. Some reversibly stopped firing after the change to an irregular pattern. Most neurons with regular spontaneous activity (simple spiking) showed decreased firing rates and more irregular intervals during pentobarbital. The results also suggest some involvement of gamma-aminobutyric acid type A receptors in the pentobarbital effects.