title: KCNQ Potassium Channels Modulate Sensitivity of Skin Down-hair (D-hair) Mechanoreceptors.
abstract: M-current-mediating KCNQ (Kv7) channels play an important role in regulating the excitability of neuronal cells, as highlighted by mutations in Kcnq2 and Kcnq3 that underlie certain forms of epilepsy. In addition to their expression in brain, KCNQ2 and -3 are also found in the somatosensory system. We have now detected both KCNQ2 and KCNQ3 in a subset of dorsal root ganglia neurons that correspond to D-hair Aδ-fibers and demonstrate KCNQ3 expression in peripheral nerve endings of cutaneous D-hair follicles. Electrophysiological recordings from single D-hair afferents from Kcnq3(-/-) mice showed increased firing frequencies in response to mechanical ramp-and-hold stimuli. This effect was particularly pronounced at slow indentation velocities. Additional reduction of KCNQ2 expression further increased D-hair sensitivity. Together with previous work on the specific role of KCNQ4 in rapidly adapting skin mechanoreceptors, our results show that different KCNQ isoforms are specifically expressed in particular subsets of mechanosensory neurons and modulate their sensitivity directly in sensory nerve endings.
authors.affiliation: From the Leibniz-Institut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Robert-Rössle-Strasse 10, 13125 Berlin and.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schütze
authors.affiliation: From the Leibniz-Institut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Robert-Rössle-Strasse 10, 13125 Berlin and.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Orozco
authors.affiliation: From the Leibniz-Institut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Robert-Rössle-Strasse 10, 13125 Berlin and; Neurocure Cluster of Excellence, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany. Electronic address: Jentsch@fmp-berlin.de.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Jentsch
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism; D017353:Gene Deletion; D015870:Gene Expression; D018859:Hair Follicle / Q000294:innervation*; D051658:KCNQ2 Potassium Channel / Q000235:genetics / Q000378:metabolism*; D051659:KCNQ3 Potassium Channel / Q000235:genetics / Q000378:metabolism*; D008465:Mechanoreceptors / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D012867:Skin / Q000294:innervation*
chemical_list: D051658:KCNQ2 Potassium Channel; D051659:KCNQ3 Potassium Channel
keywords: M-current; electrophysiology; ion channel; mechanotransduction; mouse genetics; neurobiology; potassium channel; skin-nerve preparation