Rare and spatially segregated release sites mediate a synaptic interaction between two identified network neurons

摘要: Laser-scanning confocal microscopy (LSCM), electron microcopy (EM), and cellular electrophysiology were used in combination to study the structural basis of an inhibitory synapse between two identified neurons same network. To achieve this, we examined chemical belonging lobster (Homarus gammarus) pyloric network: dilator (PD) lateral (LP) neurons. In order visualize simultaneously these neurons, intrasomatic injection Lucifer Yellow (LY) one rhodamine/horseradish peroxydase (HRP) other. Under LSCM, found only zones close apposition a restricted part neuritic tree network Then, within zones, synaptic release sites searched using EM. this end, photoconversion LY with immunogold development HRP DAB performed on previously observed preparations. Structural evidence was for site per zone. confirm result, because contact always segregated dendrites, laser photoablation selectively delete, either pre- or postsynaptically, branches which located. both cases, such restrictive ablation completely abolished functional interaction Our results therefore demonstrate that is essential operation neural relies very few localized highly each neuron's dendritic arbor. © 2002 Wiley Periodicals, Inc. J Neurobiol 50: 150–163, 2002; DOI 10.1002/neu.10023