Mechanical sensitivity and electrophysiological properties of acutely dissociated dorsal root ganglion neurons of rats

NEUROSCIENCE LETTERS

卷:634

Article

Viatchenko-Karpinski, Viacheslav¹  Gu, Jianguo G.¹ 

[1] Univ Alabama Birmingham, Coll Med, Dept Anesthesiol & Perioperat Med, 901 19TH St South,BMR 2 210, Birmingham, AL 35294 USA

关键词: Mechanotransduction;    Pain;    Piezo2;    Mechanically activated channels;    Dorsal root ganglion;   

DOI  :  10.1016/j.neulet.2016.10.011

来源: Elsevier

【 摘 要 】

Primary afferent fibers use mechanically activated (MA) currents to transduce innocuous and noxious mechanical stimuli. However, it is largely unknown about the differences in MA currents between the afferents for sensing innocuous and noxious stimuli. In the present study, we used dorsal root ganglion (DRG) neurons acutely dissociated from rats and studied their MA currents and also their intrinsic membrane properties. Recorded from small-sized DRG neurons, we found that most of these neurons were mechanically sensitive (MS) showing MA currents. The MS neurons could be classified into nociceptive-like mechanically sensitive (Noci-MS) and non-nociceptive-like mechanically sensitive (nonNoci-MS) neurons based on their action potential shapes. Noci-MS neurons responded to mechanical stimulation with three types of MA currents, rapidly adapting (RA), intermediately adapting (IA), and slowly adapting (SA) currents. In contrast, almost all nonNoci-MS neurons showed RA current type in response to mechanical stimulation. Mechanical thresholds had a broad range for both nonNoci-MS and Noci-MS neurons, and the thresholds were not significantly different between them. However, MA current densities were significantly smaller in Noci-MS than in nonNoci-MS neurons. Noci-MS and nonNoci-MS neurons also showed significant differences in their electrophysiological properties including action potential (AP) thresholds and AP firing patterns. These differences may contribute to the differential sensory encoding for innocuous and noxious mechanical stimuli. (C) 2016 Published by Elsevier Ireland Ltd.

【 授权许可】

Free