title: Inducing plasticity of astrocytic receptors by manipulation of neuronal firing rates.
abstract: Close to two decades of research has established that astrocytes in situ and in vivo express numerous G protein-coupled receptors (GPCRs) that can be stimulated by neuronally-released transmitter. However, the ability of astrocytic receptors to exhibit plasticity in response to changes in neuronal activity has received little attention. Here we describe a model system that can be used to globally scale up or down astrocytic group I metabotropic glutamate receptors (mGluRs) in acute brain slices. Included are methods on how to prepare parasagittal hippocampal slices, construct chambers suitable for long-term slice incubation, bidirectionally manipulate neuronal action potential frequency, load astrocytes and astrocyte processes with fluorescent Ca(2+) indicator, and measure changes in astrocytic Gq GPCR activity by recording spontaneous and evoked astrocyte Ca(2+) events using confocal microscopy. In essence, a "calcium roadmap" is provided for how to measure plasticity of astrocytic Gq GPCRs. Applications of the technique for study of astrocytes are discussed. Having an understanding of how astrocytic receptor signaling is affected by changes in neuronal activity has important implications for both normal synaptic function as well as processes underlying neurological disorders and neurodegenerative disease.
authors.affiliation: Graduate Program in Neuroscience, University of California Riverside.
authors.forename: Alison X
authors.initials: AX
authors.lastname: Xie
authors.affiliation: Graduate Program in Neuroscience, University of California Riverside.
authors.forename: Kelli
authors.initials: K
authors.lastname: Lauderdale
authors.affiliation: Graduate Program in Neuroscience, University of California Riverside.
authors.forename: Thomas
authors.initials: T
authors.lastname: Murphy
authors.affiliation: Graduate Program in Neuroscience, University of California Riverside.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Myers
authors.affiliation: Department of Cell Biology and Neuroscience, University of California Riverside; Center for Glial-Neuronal Interactions, University of California Riverside; toddf@ucr.edu.
authors.forename: Todd A
authors.initials: TA
authors.lastname: Fiacco
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D051379:Mice; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000379:methods; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism
chemical_list: D043562:Receptors, G-Protein-Coupled; D018094:Receptors, Metabotropic Glutamate