title: AII (Rod) amacrine cells form a network of electrically coupled interneurons in the mammalian retina.
abstract: AII (rod) amacrine cells in the mammalian retina are reciprocally connected via gap junctions, but there is no physiological evidence that demonstrates a proposed function as electrical synapses. In whole-cell recordings from pairs of AII amacrine cells in a slice preparation of the rat retina, bidirectional, nonrectifying electrical coupling was observed in all pairs with overlapping dendritic trees (average conductance approximately 700 pS). Coupling displayed characteristics of a low-pass filter, with no evidence for amplification of spike-evoked electrical postsynaptic potentials by active conductances. Coincidence detection, as well as precise temporal synchronization of subthreshold membrane potential oscillations and TTX-sensitive spiking, was commonly observed. These results indicate a unique mode of operation and integrative capability of the network of AII amacrine cells.
authors.affiliation: University of Bergen, Department of Anatomy and Cell Biology, Arstadveien 19, N-5009 Bergen, Norway.
authors.forename: Margaret Lin
authors.initials: ML
authors.lastname: Veruki
authors.forename: Espen
authors.initials: E
authors.lastname: Hartveit
mesh_terms: D000200:Action Potentials / Q000502:physiology; D025042:Amacrine Cells / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D017629:Gap Junctions / Q000378:metabolism*; D066298:In Vitro Techniques; D009415:Nerve Net / Q000166:cytology / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D012160:Retina / Q000166:cytology / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D013997:Time Factors