The functional roles of chemical coupling and gap junction between horizontal cells in the catfish retina

For the investigation of the roles of chemical coupling and gap junction between horizontal cells, the spatio-temporal properties of horizontal cell network were studied using conventional physiological recording techniques and computer simulations. Our results show that the spatial integration of light signal may be mainly performed by electrical junctions, and the temporal integration may be regulated by chemical coupling between horizontal cells. This means that visual information can be modulated spatio-temporally by pathways involving both electrical coupling composed of gap junctions and chemical coupling composed of GABAergic synapses in outer retina of the low vertebrate.