My laboratory emphasizes electrophysiological and imaging techniques (including whole-cell voltage-clamp, perforated patch, single channel recordings, and self-referencing recording methodologies) to examine the characteristics of nerve cells and to probe the effects of neurotransmitters and neuromodulators on retinal neurons and glia. Electrophysiological and molecular biological characterization of transport proteins of retinal neurons and glial cells has been and continues to be a major focus of work in the lab, and we are currently exploring the modulation of GABA transport induced by extracellulary-applied ATP. The Xenopus oocyte expression system is also being used to examine the properties of transporters cloned from the retina of several species including the skate. An additional focus for the laboratory is the use of a self-referencing, noninvasive microelectrode system to examine the transport of a variety of physiologically relevant compounds by retinal neuron and glia. Using this system, we have been able to detect the extrusion of calcium and hydrogen ions from single isolated retinal neurons and glia been able to examine the consumption of oxygen from individual photoreceptors, and have also been able to detect the release of nitric oxide from isolated macrophage cells stimulated with gamma-interferon. Our future plans include the use of this system to examine the release of nitric oxide from identified retinal cells.
Ultimately, we hope that these studies will shed light on the cellular and molecular processes that enable visual perception, and believe that our findings will have general applicability to neurons in far removed parts of the nervous system.