Gender	Male
E-mail	brady.trexler@mssm.edu
Education and Training	Ph.D., Albert Einstein College of Medicine

Education and Training	Ph.D., Albert Einstein College of Medicine

Synaptic pathways in the Mammalian retina

Research in my laboratory is focused on understanding how the neural circuits in the mammalian retina encode the visual scene for transmission to the rest of the brain. Some of the most complex synapses in the nervous system occur in the retina, making it of great interest to those studying neuroanatomy and physiology as well as information processing and computation.

Our detailed knowledge of the anatomy of neural circuits in the retina has provided us with strong clues about their function, and we are now poised to address how each cell??s synapses and membrane conductances shape incoming visual signals. The laboratory??s research addresses such questions as: When are specific synapses active and how does adaptation affect the role of a synapse? How do voltage dependent conductances affect a cell??s output and the computational abilities of networks of coupled cells? Is the coupling strength of networks dynamic? We address these questions by using single and dual whole cell patch clamp recording of identified neurons in in vitro slice preparations of rabbit retina together with confocal imaging of neurons labeled with immunological markers or injected dyes.

In addition, the laboratory is involved in the design and testing of artificial photoreceptors as a possible therapy for retinitis pigmentosa and other degenerative diseases. Working in collaboration with the Texas Center for Superconductivity and Applied Materials (TcSAM), we are examining the mechanism of action and feasibility of thin layer photovoltaic devices that can be implanted in the retina as a means to activate neurons downstream of the photoreceptors. We recently developed a novel in vitro experimental system that will aid in these endeavors.

Petrides A, Trexler EB. Differential output of the high- sensitivity rod photoreceptor: AII amacrine pathway. J Comp Neurol 2008; 507(5): 1653-1662.

Zomorrodian A, Wu NJ, Song S, Ignatiev A, Trexler EB, Garcia CA. Micro Photo Detector Fabricated of Ferroelectric-Metal Heterostructure. Jpn. J. Appl 2005; 44(8): 6105-6108.

Trexler B, Li W, Massey SC. Simultaneous contribution of two rod pathways to AII amacrine and cone bipolar cell light response. J Neurophysiol 2005 Nov; 93(3): 1476-85.

Kronengold J, Trexler EB, Bargiello TA, Verselis VK. Single-channel SCAM identifies pore-lining residues in the first extracellular loop and first transmembrane domains of Cx46 hemichannels. J Gen Physiol 2003; 122(4): 389-405.

Li W, Trexler EB, Massey SC. Glutamate receptors at the rod bipolar terminal dyad synapse. J Comp Neurol 2002; 448(3): 230-48.

Zhang J, Li W, Trexler EB, Massey SC. Confocal analysis of reciprocal feedback at rod bipolar terminals in the rabbit retina. J Neurosci 2002; 22(24): 10871-82.

Trexler EB, Li W, Mills SL, Massey SC. Coupling from AII amacrine cells to ON cone bipolar cells is bidirectional. J Comp Neurol 2001; 437(4): 408-22.

Trexler EB, Verselis VK. The study of connexin hemichannels (connexons) in Xenopus oocytes. Methods Mol Biol 2001; 154: 341-55.

Trexler EB, Bukauskas FF, Kronengold J, Bargiello TA, Verselis VK. The first extracellular loop domain is a major determinant of charge selectivity in connexin46 channels. Biophys J 2000; 79(6): 3036-51.

Trexler EB, Bukauskas FF, Bennett M, Bargiello TA, Verselis VK. Rapid and direct effects of pH on connexins revealed by the Cx46 hemichannel preparation. J. Gen Phys 1999; 113(5): 721-42.