Synaptic connections of starburst amacrine cells and localization of acetylcholine receptors in primate retinas

J Comp Neurol. 2003 Jun 16;461(1):76-90. doi: 10.1002/cne.10672.

Abstract

Starburst amacrine cells in the macaque retina were studied by electron microscopic immunohistochemistry. We found that these amacrine cells make a type of synapse not described previously; they are presynaptic to axon terminals of bipolar cells. We also confirmed that starburst amacrine cells are presynaptic to ganglion cell dendrites and amacrine cell processes. In order to determine the functions of these synapses, we localized acetylcholine receptors using a monoclonal antibody (mAb210) that recognizes human alpha3- and alpha5-containing nicotinic receptors and also antisera against the five known subtypes of muscarinic receptors. The majority of the mAb210-immunoreactive perikarya were amacrine cells and ganglion cells, but a subpopulation of bipolar cells was also labeled. A subset of bipolar cells and a subset of horizontal cells were labeled with antibodies to M3 muscarinic receptors. A subset of amacrine cells, including those that contain cholecystokinin, were labeled with antibodies to M2 receptors. Taken together, these results suggest that acetylcholine can modulate the activity of retinal ganglion cells by multiple pathways.

Publication types

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

MeSH terms

  • Acetylcholine / metabolism
  • Amacrine Cells / metabolism
  • Amacrine Cells / ultrastructure*
  • Animals
  • Eye / innervation
  • Immunohistochemistry
  • Interneurons / physiology
  • Macaca mulatta / physiology*
  • Microscopy, Electron
  • Receptors, Cholinergic / metabolism*
  • Retina / metabolism
  • Retina / ultrastructure*
  • Retinal Ganglion Cells / physiology
  • Synapses / metabolism
  • Synapses / ultrastructure*
  • Synaptic Transmission / physiology
  • Tissue Distribution
  • gamma-Aminobutyric Acid / metabolism

Substances

  • Receptors, Cholinergic
  • gamma-Aminobutyric Acid
  • Acetylcholine