Passive electrical properties of spontaneously active neurons in the nucleus reticularis gigantocellularis of the cat.

We evaluated in chloralose-urethane anesthetized cats the passive electrical properties of 25 spontaneously active neurons in the nucleus reticularis gigantocellularis (NRGC) of the medulla oblongata. Compared to other mammalian brain regions, these reticular cells in general possessed higher input resistance, shorter membrane time constant and first equalizing time constant, and longer somatodendritic electrotonic length factor. It is discussed that, by providing a synaptic machinery for quick and sensitive response to afferent inputs and an efficacious interplay between temporal and spatial summation, these electrical membrane properties may account for the spontaneous and irregular discharge pattern characteristic of the NRGC neurons.