title: A single mechanism driving both inactivation and adaptation in rapidly adapting currents of DRG neurons?
abstract: Rapidly adapting (RA) currents expressed in dorsal root ganglia somatosensory neurons reduce their amplitude in response to prolonged and/or repeated mechanical stimulation. Both inactivation of mechanotransducer channels and adaptation of the force acting on the channels have been suggested to independently decrease RA currents. However, these two mechanisms have similar kinetics and dependence on calcium and voltage. These experimental findings suggest that a single mechanism might underlie both. We constructed a simple Hodgkin-Huxley-type model with a single gating variable driving both inactivation and adaptation to test this hypothesis. Predictions of the model successfully describe key features of mechanical activation as well as inactivation, adaptation, and recovery. The model thus supports the possibility of a single mechanism driving inactivation and adaptation in RA currents. On its own, the model can be integrated into higher-order models of touch receptors because of its accurate simulation of RA currents.
authors: Department of Apiculture, Agricultural Institute of Slovenia, Hacquetova ul. 17, 1000, Ljubljana, Slovenia.
authors: Janez
authors: J
authors: Prešern
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000, Ljubljana, Slovenia.
authors: Aleš
authors: A
authors: Škorjanc
authors: Faculty of Natural sciences and Engineering, University of Ljubljana, Aškerčeva cesta 12, 1000, Ljubljana, Slovenia.
authors: Tomaž
authors: T
authors: Rodič
authors: Institute for Neurobiology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany. jan.benda@uni-tuebingen.de.
authors: Jan
authors: J
authors: Benda
mesh_terms: D000222:Adaptation, Physiological; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology*; D006801:Humans; D015640:Ion Channel Gating; D008564:Membrane Potentials; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques
keywords: Adaptation; DRG neuron; Inactivation; Mechanoreceptor; Model; RA current