This award supports Dr. Stuart A. Lipton and a colleague at Children's Hospital Corporation to collaborate in research on retinal ganglion cells with Dr. Heinz Wassle, Department of Neuroanatomy, Max Planck Institute for Brain Research in Frankfurt, West Germany. The general objective of their research is to gain a better understanding of the interactions of neurotransmitters in the mammalian retina. The particular objective of their collaboration is to identify the nature of the chemicals operating in specific synapses onto retinal ganglion cells. The U.S. team has developed uniquely successful techniques for identifying and culturing in vitro mature retinal ganglion cells from mammals. They have also adapted the patch-clamp recording technique to this system. The German group has perfected methods to identify and culture in vitro mature retinal bipolar cells, a major cell type that synapses onto retinal ganglions, and they are performing patch-clamp experiments on these bipolar neurons. The use of these two disparate neuronal cell types from the retina is central to the collaboration; maintaining a particular neuron in culture from a mature mammalian central nervous system is quite difficult. Through joint experiments, they will co-culture the two types of neurons and produce synapses between them. Then, glutamate-like substances previously found to affect solitary ganglion cells will be tested for their effects on endogenous synaptic activity in ganglion cells located among clusters of other retinal cells in cultures. The proposed joint experiments on co-cultured retinal ganglion and bipolar cells will enable these collaborators to verify the effects of putative glutamate-like neurotransmitters at synapses. Their research should result in characterizing the first known chemical transmitter between identified neurons entirely within the mammalian brain. This will contribute in a significant way to improved understanding of the mammalian central nervous system.
