Distinct Distribution Patterns of Pain-Responsive and Itch-Sensitive Nerve Terminal in Mouse Skin
10.11969/j.issn.1673-548X.2025.08.006
- VernacularTitle:痛痒觉神经皮肤支配的组织特异性
- Author:
Liting CHEN
1
;
Han LI
;
Shudi ZHOU
Author Information
1. 200025 上海交通大学基础医学院解剖学与生理学系
- Publication Type:Journal Article
- Keywords:
Mouse;
Skin;
Pain-sensitive nerve;
Itch-sensitive nerve
- From:
Journal of Medical Research
2025;54(8):26-33,55
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the distribution characteristics and innervation patterns of pain-and itch-sensing nerves in dif-ferent regions of skin tissue.Methods Using Trpv1Cre;Ai9 and SstCre;Ai9 transgenic mouse systems,to analyze the distribution and in-nervation patterns of transient receptor potential vanilloid 1(TRPV1+)pain-sensing nerves and somatostatin(SST+)itch-sensing nerves in the skin of the forelimbs,hindlimbs and dorsal abdomen.Immunofluorescence staining was employed to quantitatively detect the distribution ratios of these two types of sensory neurons in the dorsal root ganglia(DRG).Results Free nerve terminal of both pain-and itch-sensing nerves were observed in the epidermal and dermal layers of skin tissue across all regions,but their morphological and distribution characteristics differed significantly.In the dermis,the two types of nerve fibers exhibited a parallel innervation pattern,while in the epidermis,their distribution tended to be more dispersed.Pain-sensing nerve terminal displayed a dense,filamentous distribu-tion,whereas itch-sensing nerve terminal were arranged in a sparse,bead-like pattern.In the DRG,the proportion of pain-sensing neuronal cell bodies was 76.13％±2.33％,while itch-sensing neuronal cell bodies accounted for only 7.58％±2.59％.Additionally,TRPV 1 was not only expressed in pain-sensing nerve fibers but also showed high expression in the stratum corneum,dermis,and inter-muscular layers of the plantar skin.In contrast,SST was primarily expressed in itch-sensing nerve fibers,with minor expression in peri-follicular cells.Conclusion Pain-and itch-sensing nerve fibers exhibit distinct innervation patterns in the skin.The widespread and dense distribution of pain-sensing nerve terminal may provide a structural basis for the rapid detection of potential noxious stimuli.This study offers morphological evidence to clarify the regulatory mechanisms of peripheral sensory nervous system function.
