title: Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex.
abstract: In rodent cortex GABAA receptor (GABAAR)-mediated synapses are a significant source of input onto GABA neurons, and the properties of these inputs vary among GABA neuron subtypes that differ in molecular markers and firing patterns. Some features of cortical interneurons are different between rodents and primates, but it is not known whether inhibition of GABA neurons is prominent in the primate cortex and, if so, whether these inputs show heterogeneity across GABA neuron subtypes. We thus studied GABAAR-mediated miniature synaptic events in GABAergic interneurons in layer 3 of monkey dorsolateral prefrontal cortex (DLPFC). Interneurons were identified on the basis of their firing pattern as fast spiking (FS), regular spiking (RS), burst spiking (BS), or irregular spiking (IS). Miniature synaptic events were common in all of the recorded interneurons, and the frequency of these events was highest in FS neurons. The amplitude and kinetics of miniature inhibitory postsynaptic potentials (mIPSPs) also differed between DLPFC interneuron subtypes in a manner correlated with their input resistance and membrane time constant. FS neurons had the fastest mIPSP decay times and the strongest effects of the GABAAR modulator zolpidem, suggesting that the distinctive properties of inhibitory synaptic inputs onto FS cells are in part conferred by GABAARs containing α1 subunits. Moreover, mIPSCs differed between FS and RS interneurons in a manner consistent with the mIPSP findings. These results show that in the monkey DLPFC GABAAR-mediated synaptic inputs are prominent in layer 3 interneurons and may differentially regulate the activity of different interneuron subtypes.
authors.affiliation: Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands;
authors.forename: Diana C
authors.initials: DC
authors.lastname: Rotaru
authors.affiliation: Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania;
authors.forename: Cameron
authors.initials: C
authors.lastname: Olezene
authors.affiliation: Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania;
authors.forename: Takeaki
authors.initials: T
authors.lastname: Miyamae
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania; and.
authors.forename: Nadezhda V
authors.initials: NV
authors.lastname: Povysheva
authors.affiliation: Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, St. Petersburg, Russia.
authors.forename: Aleksey V
authors.initials: AV
authors.lastname: Zaitsev
authors.affiliation: Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania;
authors.forename: David A
authors.initials: DA
authors.lastname: Lewis
authors.affiliation: Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania; gburgos@pitt.edu.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Gonzalez-Burgos
mesh_terms: D000200:Action Potentials; D000818:Animals; D005260:Female; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D059330:GABAergic Neurons / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D053444:Inhibitory Postsynaptic Potentials; D007395:Interneurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D008253:Macaca mulatta; D008297:Male; D055369:Miniature Postsynaptic Potentials; D017397:Prefrontal Cortex / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D011725:Pyridines / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D000077334:Zolpidem; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D058785:GABA-A Receptor Agonists; D011725:Pyridines; D005680:gamma-Aminobutyric Acid; D000077334:Zolpidem
keywords: GABAA receptor; disinhibition; dorsolateral prefrontal cortex; inhibitory postsynaptic potential; interneuron; primate