title: Voltage-gated potassium channels involved in regulation of physiological function in MrgprA3-specific itch neurons.
abstract: Itch is described as an unpleasant or irritating skin sensation that elicits the desire or reflex to scratch. MrgprA3, one of members of the Mrgprs family, is specifically expressed in a subpopulation of dorsal root ganglion (DRG) in the peripheral nervous system (PNS). These MrgprA3-expressing DRG neurons have been identified as itch-specific neurons. They can be activated by the compound, chloroquine, which is used as a drug to treat malaria. In the present study, we labeled these itch-specific neurons using the method of molecular genetic markers, and then studied their electrophysiological properties. We also recorded the cutaneous MrgprA3(-) neurons retrogradely labeled by Dil dye (MrgprA3(-)-Dil). We first found that MrgprA3(+) neurons have a lower excitability than MrgprA3(-) neurons (MrgprA3(-)-non-Dil and MrgprA3(-)-Dil). The number of action potential (AP) was reduced more obviously in MrgprA3(+) neurons than that of in MrgprA3(-) neurons. In most cases, MrgprA3(+) neurons only generated single AP; however, in MrgprA3(-) neurons, the same stimulation could induce multiple AP firing due to the greater voltage-gated potassium (Kv) current existence in MrgprA3(+) than in MrgprA3(-) neurons. Thus, Kv current plays an important role in the regulation of excitability in itch-specific neurons.
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China; College of Biology and Environmental Sciences, Jishou University, Jishou, China.
authors.forename: Min
authors.initials: M
authors.lastname: Tang
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China; College of Basic Medicine, Guangxi University of Chinese Medicine, Nanning, China.
authors.forename: Guanyi
authors.initials: G
authors.lastname: Wu
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Zhongli
authors.initials: Z
authors.lastname: Wang
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Niuniu
authors.initials: N
authors.lastname: Yang
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Shi
authors.affiliation: College of Biology and Environmental Sciences, Jishou University, Jishou, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: He
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Chan
authors.initials: C
authors.lastname: Zhu
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Guang
authors.initials: G
authors.lastname: Yu
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Changming
authors.initials: C
authors.lastname: Wang
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Yuan
authors.affiliation: Department of Anesthesiology, Washington University in St. Louis, USA.
authors.forename: Qin
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University Schools of Medicine, Baltimore, MD, USA.
authors.forename: Yun
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Xinzhong
authors.initials: X
authors.lastname: Dong
authors.affiliation: College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing, China. Electronic address: zongxiangtang@njutcm.edu.cn.
authors.forename: Zongxiang
authors.initials: Z
authors.lastname: Tang
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000235:genetics*; D000596:Amino Acids / Q000008:administration & dosage; D000818:Animals; D055592:Biophysical Phenomena / Q000187:drug effects / Q000235:genetics; D001703:Biophysics; D002478:Cells, Cultured; D004558:Electric Stimulation; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000494:pharmacology; D026902:Potassium Channel Blockers / Q000494:pharmacology; D024642:Potassium Channels, Voltage-Gated / Q000502:physiology*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D019789:Tetraethylammonium / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D008164:Luminescent Proteins; C546475:MrgprA3 protein, mouse; D026902:Potassium Channel Blockers; D024642:Potassium Channels, Voltage-Gated; D043562:Receptors, G-Protein-Coupled; C098463:dolaisoleucine; D019789:Tetraethylammonium; D011188:Potassium
keywords: DRG; Itch; Kv current; MrgprA3