Unique functional properties of on and off pathways in the developing mammalian retina

J Neurosci. 2001 Jun 15;21(12):4310-7. doi: 10.1523/JNEUROSCI.21-12-04310.2001.


In the mature retina, the dendrites of On and Off ganglion cells are segregated into separate sublaminas of the inner plexiform layer, but early in development these processes are multistratified, ramifying more widely within this synaptic layer. The dendritic pattern exhibited by immature ganglion cells suggests that there may be a functional convergence of On and Off pathways in the developing retina, but previous studies have provided evidence against this. Here we demonstrate by patch-clamp recordings and dye filling that ganglion cells with multistratified dendrites respond to the onset, as well as the offset, of light. We further show that, in the dark-adapted retina, the glutamate analog 2-amino-4-phosphonobutric acid abolishes On and Off discharges in ganglion cells with multistratified dendrites. In contrast, in cells with stratified dendrites, this drug selectively blocks On responses. These findings provide evidence for unique functional attributes of On and Off pathways in the developing retina. The properties of immature ganglion cells documented here have important implications for the roles ascribed to neuronal activity in refining connections during the early development of the visual system.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / physiology
  • Adaptation, Ocular / physiology
  • Aging / physiology
  • Aminobutyrates / pharmacology
  • Animals
  • Cell Count
  • Dendrites / physiology
  • Excitatory Amino Acid Agonists / pharmacology
  • Ferrets
  • In Vitro Techniques
  • Patch-Clamp Techniques
  • Photic Stimulation
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Retina / drug effects
  • Retina / growth & development*
  • Retina / physiology*
  • Retinal Ganglion Cells / classification
  • Retinal Ganglion Cells / cytology
  • Retinal Ganglion Cells / drug effects
  • Retinal Ganglion Cells / physiology
  • Visual Pathways / drug effects
  • Visual Pathways / physiology*


  • Aminobutyrates
  • Excitatory Amino Acid Agonists
  • 2-amino-4-phosphonobutyric acid