Interaction of cone signals on L-type horizontal cell in carp retina: experiments and modeling

Intracellular recordings were made from the luminosity type cone driven horizontal cells (LHCs) in the isolated carp retina and model analysis was performed to investigate possible mechanisms underlying the interaction of different cone signals converging onto these cells. It was observed that a green background light enhanced the LHC's red response, and such enhancement was closely related to the activation of green cones. Model analysis showed that the activity of both glutamate- and GABA-related pathways were potentiated during green background illumination. GABA application did not abolish the response enhancement. It is speculated that the extent of the LHC's response enhancement may be determined by the balance of the increased activity between the feedforward and feedback pathways.