title: Interaction of Intrinsic and Synaptic Currents Mediate Network Resonance Driven by Layer V Pyramidal Cells.
abstract: Cortical oscillations modulate cellular excitability and facilitate neuronal communication and information processing. Layer 5 pyramidal cells (L5 PYs) drive low-frequency oscillations (<4 Hz) in neocortical networks in vivo. In vitro, individual L5 PYs exhibit subthreshold resonance in the theta band (4-8 Hz). This bandpass filtering of periodic input is mediated by h-current (Ih) and m-current (IM) that selectively suppress low-frequency input. It has remained unclear how these intrinsic properties of cells contribute to the emergent, network oscillation dynamics. To begin to close this gap, we studied the link between cellular and network mechanisms of network resonance driven by L5 PYs. We performed multielectrode array recordings of network activity in slices of medial prefrontal cortex from the Thy1-ChR2-eYFP line and activated the network by temporally patterned optogenetic suprathreshold stimulation. Networks driven by stimulation of L5 PYs exhibited resonance in the theta band. We found that Ih and IM play a role in resonant suprathreshold network response to depolarizing stimuli. The action of Ih in mediating resonance was dependent on synaptic transmission while that of IM was not. These results demonstrate how synergistic interaction of synaptic and intrinsic ion channels contribute to the response of networks driven by L5 PYs.
authors: Department of Psychiatry.|Joint UNC-NCSU Department of Biomedical Engineering.
authors: Stephen L
authors: SL
authors: Schmidt
authors: Department of Psychiatry.|Neurobiology Curriculum.
authors: Christopher R
authors: CR
authors: Dorsett
authors: Department of Biology.
authors: Apoorva K
authors: AK
authors: Iyengar
authors: Department of Psychiatry.|Joint UNC-NCSU Department of Biomedical Engineering.|Neurobiology Curriculum.|Department of Cell Biology and Physiology.|Neuroscience Center.|Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors: Flavio
authors: F
authors: Fröhlich
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D004558:Electric Stimulation / Q000379:methods; D006624:Hippocampus / Q000502:physiology; D007473:Ion Channels / Q000502:physiology; D051379:Mice; D009415:Nerve Net / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D017966:Pyramidal Cells / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*
chemical_list: D007473:Ion Channels
keywords: cortical slice; h current; m current; multielectrode array; resonance