[Excitatory postsynaptic potentials in motor neurons of rats upon stimulation of individual reticulospinal neurons].

Unit reticulo-motoneuronal EPSPs evoked by extra -- or intracellular stimulation of reticulo-spinal neurons were recorded intracellularly from rat lumbar motoneurons. Reticular neurons with fast conducting axons revealed higher probability of direct effect on motoneurons. Terminals of single reticular neurons to different motoneurons were shown to be widely distributed. Analysis of the time course of average unit EPSPs suggests proximal to soma location of some reticulo-motoneuronal synapses. Amplitude-frequency histograms of the unit EPSPs could be fitted in most cases by Poisson's or binominal distribution, suggesting the quantal nature of transmitter release.