In the Lee Martin Laboratory, we are testing the hypothesis that selective vulnerability--the phenomenon in which only certain groups of neurons degenerate in adult onset neurological disorders like amyotrophic lateral sclerosis and Alzheimer's disease--is dictated by brain regional connectivity, mitochondrial function and oxidative stress. We believe it is mediated by excitotoxic cell death resulting from abnormalities in excitatory glutamatergic signal transduction pathways, including glutamate transporters and glutamate receptors as well as their downstream intracellular signaling molecules. We are also investigating the contribution of neuronal/glial apoptosis and necrosis as cell death pathways in animal (including transgenic mice) models of acute and progressive neurodegeneration. We use a variety of anatomical and molecular neurobiological approaches, including neuronal tract-tracing techniques, immunocytochemistry, immunoblotting, antipeptide antibody production, transmission electron microscopy and DNA analysis to determine the precise regional and cellular vulnerabilities and the synaptic and molecular mechanisms that result in selective neuronal degeneration.

Research in the Raymond Koehler Lab explores cerebrovascular physiology and cerebral ischemic injury caused by stroke and cardiac arrest, using protein analysis, immunohistochemistry and histology. We also study ischemic preconditioning, neonatal hypoxic-ischemic encephalopathy and the mechanisms of abnormal cerebrovascular reactivity after ischemia. We 're examining ways to improve tissue oxygenation and seek to better understand the mechanisms that connect an increase in cerebral blood flow to neuronal activity.