title: Rod vision is controlled by dopamine-dependent sensitization of rod bipolar cells by GABA.
abstract: Dark and light adaptation of retinal neurons allow our vision to operate over an enormous light intensity range. Here we report a mechanism that controls the light sensitivity and operational range of rod-driven bipolar cells that mediate dim-light vision. Our data indicate that the light responses of these cells are enhanced by sustained chloride currents via GABA(C) receptor channels. This sensitizing GABAergic input is controlled by dopamine D1 receptors, with horizontal cells serving as a plausible source of GABA release. Our findings expand the role of dopamine in vision from its well-established function of suppressing rod-driven signals in bright light to enhancing the same signals under dim illumination. They further reveal a role for GABA in sensitizing the circuitry for dim-light vision, thereby complementing GABA's traditional role in providing dynamic feedforward and feedback inhibition in the retina.
authors: Albert Eye Research Institute, Duke University, Durham, NC 27710, USA.
authors: Rolf
authors: R
authors: Herrmann
authors: Stephanie J
authors: SJ
authors: Heflin
authors: Timothy
authors: T
authors: Hammond
authors: Bowa
authors: B
authors: Lee
authors: Jing
authors: J
authors: Wang
authors: Raul R
authors: RR
authors: Gainetdinov
authors: Marc G
authors: MG
authors: Caron
authors: Erika D
authors: ED
authors: Eggers
authors: Laura J
authors: LJ
authors: Frishman
authors: Maureen A
authors: MA
authors: McCall
authors: Vadim Y
authors: VY
authors: Arshavsky
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology; D000818:Animals; D004298:Dopamine / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D009433:Neural Inhibition / Q000502:physiology; D055254:Night Vision / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D017447:Receptors, Dopamine D1 / Q000502:physiology; D018079:Receptors, GABA / Q000502:physiology; D051245:Retinal Bipolar Cells / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: C087200:GABA-C receptor; D017447:Receptors, Dopamine D1; D018079:Receptors, GABA; D005680:gamma-Aminobutyric Acid; D004298:Dopamine