Investigating the Role of Astrocyte Signaling in Brain Function
Research Synopsis:
Approximately 50% of the mammalian brain is composed of astrocytes. These cells are present in
every region of brain, are always closely associated with neuronal elements, and exhibit a wide variety
of morphological phenotypes and neurotransmitter receptors. It is striking that while these cells
constitute the largest single population of cells in brain, we know very little concerning their role in
brain function. Many neurobiologists believe that astrocytes play a critical role in buffering extracellular
potassium levels within the narrow range required for neuronal activity. Similarly, astrocytes are
thought important in removing glutamate following its release at neuronal synapses.
A primary goal of our laboratory is to determine how astrocytes and neurons are signaling one another
and the functional outcome of neuron astrocyte conversation. Our working hypothesis is that there are
microdomains within astrocytic syncytium that interact with neuronal synapses to facilitate or to dampen
neuronal excitability and/or neurotransmission. Through a combination of 2-photon confocal imaging,
electrophysiological and molecular studies we hope to begin unraveling the role of these cells in brain
function and animal behavior.
Casper, K.B., and McCarthy, K.D. GFAP-positive progenitor cells produce neurons and oligodendrocytes throughout the CNS. (2006) Mol Cell Neurosci [in press] Abstract
Fiacco, T.A., and McCarthy, K.D. (2004) Intracellular astrocyte calcium waves in situ increase the frequency of spontaneous AMPA receptor currents in CA1 pyramidal neurons. J Neurosci 24(3): 722-32. Abstract
Lin, W., Kemper, A., McCarthy, K.D., Pytelm P., Wangm, J.P., Campbell, I.L., Utset, M.F., and Popko, B. (2004) Interferon-gamma induced medulloblastoma in the developing cerebellum. J Neurosci 24(45): 10074-83. Abstract
Nett, W.J., Oloff, S.H., and McCarthy, K.D. (2002) Hippocampal astrocytes in situ exhibit calcium oscillations that occur independent of neuronal activity. J Neurophysiol87(1): 528-537. Abstract
