Signal transmission through gap junctions is one of major communication ways between neurons.It is known that a variety of retinal neurons are extensively coupled through gap junctions and electrical coupling between these cells plays an important role in retinal information processing.Each one of any two cells making a gap junction contributes one half of the junction,named connexon,which is composed of six protein subunits (connexin,Cx) arranged radially around a central pore,through which currents flow.In this work,the expression of Cx35/36 in carp retina was studied using immunofluorescence labeling and confocal laser scanning microscopy.The specificity of the Cx35/36 antibody was confirmed by Western blot analysis.For double labeling experiments,one of the three antibodies against recoverin,PKCα or GAD65/67,specific markers respectively for cones,rod-ON bipolar cells and horizontal cells,was double-labeled together with the anti-Cx35/36 antibody.In vertical sections of carp retina,Cx35/36 antibodies resulted in distinct round or elongated punctuate staining or plagues in both the outer and inner plexiform layers (OPL and IPL).