Acta Anatomica Sinica ›› 2016, Vol. 47 ›› Issue (5): 583-590.doi: 10.16098/j.issn.0529-1356.2016.05.002

• Neurobiology • Previous Articles     Next Articles

Distribution features of itch-specific neurons in dorsal root ganglion in mice

TANG Min 1,2 GENG Xiao1 YU Lei1 ZHU Chan1 YANG Yan1 WANG Chang-ming1 YU Guang1 TANG Zong-xiang 1*   

  1. 1. College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China; 2. College of Biology and Environmental Sciences, Jishou University, Hu’nan Jishou 416000, China

  • Received:2016-05-09 Revised:2016-06-20 Online:2016-10-06 Published:2016-10-06
  • Contact: TANG Zong-xiang E-mail:zongxiangtang@njutcm.edu.cn
  • Supported by:

    Itch functional analysis of Mrgprs and target screening of pruritogenic substances from natrual products

Abstract:

Objective To observe the distribution features of itch-specific MrgprA3neurons located in the dorsal root ganglion (DRG).Methods The MrgprA3+neurons were specifically labeled by enhaced green fluorescence protein(EGPF) and tdTomato using a genetic method. The skin and DRG tissues in the 3 adult homogenous transgenic Mrgpra3 EGFP-Cre ;ROSA26 tdTomato mice were collected. The peripheral MrgprA3+fibers innervating the skin were imaged by using confocal imaging technology. The distribution of MrgprA3+neurons in the intact DRG tissue was observed using two-photo imaging technology.Results The MrgprA3+fibers in cheek, back and paw skins were densely and widely distributed with clearly coarse and long features. By contrast, the MrgprA3+fibers in neck and abdomen skins were sparsely distributed with short and dotted features. The MrgprA3+fibers were distributed in both hairy and glabrous skins and showed different properties in various parts of body. Almost all of MrgprA3+neurons belonged to small diameter sensory neurons and located in the cervical, thoracic, lumbar and sacral DRG tissues. The Z axis imaging depth was 350μm in cervical DRG, 250μm in thoracic DRG, 400μm in lumbar DRG and 200μm in sacral DRG. Three dimensional spatial distributions of MrgprA3+neurons in various DRG tissues had significant differences.Conclusion The MrgprA3+fibers in various peripheral skin and MrgprA3+neurons located in intact DRG tissues show different distribution properties. The differences in the distribution of itch neurons and terminals may be the structural basis for the differences in the presence of itch sensation in different areas.

Key words: Itch-specific neuron, Dorsal root ganglion, Confocal imaging, Twophoto imaging, Transgenic mouse