COUNTING QUANTA - DIRECT MEASUREMENTS OF TRANSMITTER RELEASE AT A CENTRAL SYNAPSE

Contradictory hypotheses regarding the nature of synaptic transmission in the CNS have arisen from indirect methods of quantal analysis. In this study, we directly count the quanta released following nerve stim ulation to examine synaptic transmission at a fast glutamatergic synap se in the mammalian auditory brainstem. Our results demonstrate the re lationship between spontaneous and nerve-evoked synaptic events, indic ate that asynchronous transmitter release governs the time course of e voked transmission, and show that the stochastic quantal release proce ss, as originally proposed at the neuromuscular junction, is highly co nserved at this central synapse.