Peter D. Lukasiewicz, Ph.D.
Ophthalmology and Visual Sciences
Molecular Cell Biology Program
We study how synaptic interactions in the retina mediate the first stages of visual information processing. The vertebrate retina is ideally suited for studying synaptic interactions. It is an accessible part of the central nervous system, which can be stimulated physiologically with light. The laboratory studies how synaptic signals mediated by subtypes of GABA and glutamate receptors contribute to visual processing in specific retinal circuits. A major interest is in how excitatory signals mediated by glutamate are affected by receptor properties and uptake mechanisms. Glutamate transporters and receptor desensitization may play a more significant role in signal shaping in the retina than in most other parts of the CNS, making the retina a model system for investigating these phenomena. We are also investigating how inhibitory signals mediated by GABAA and GABAC receptors affect visual information processing. GABAC receptors are unique because they are abundant in the retina, but sparsely distributed in other parts of the CNS. Using pharmacological techniques and knockout mice, we found that these subtypes of GABA receptors have different functional properties and are differentially distributed on particular types of neurons, where each receptor shapes visual signals in distinct ways. The the synaptic basis of visual processing is studied by making whole-cell patch recordings from morphologically identified neurons in the retinal slice preparation. These studies will help define how the neurotransmitters glutamate and GABA function in specific neural circuits to process different forms of visual information.
Ichinose T, Lukasiewicz PD. Ambient light regulates sodium channel activity to dynamically control retinal signaling. J Neurosci 2007 27:4756-4764.
Eggers ED, Lukasiewicz PD. Receptor and transmitter release properties set the time course of retinal inhibition. J Neurosci 2006 26:9413-9425.
Eggers ED and Lukasiewicz PD. GABAA, GABAC and glycine receptor-mediated inhibition differentially affects light-evoked signaling from mouse retinal rod bipolar cells. J Physiol 2006 572:215-225.
Sagdullaev BT, McCall MA and Lukasiewicz PD. Presynaptic inhibition modulates spillover, creating distinct dynamic response ranges of sensory output. Neuron 2006 50:923-935.
Lukasiewicz PD. Synaptic mechanisms that shape visual signaling at the inner retina. Prog Brain Res 2005 147:205-218. Review.
Last Updated: 8/4/2011 10:46:09 AM