Upregulation of Cav3.2 T-type calcium channels in adjacent intact L4 dorsal root ganglion neurons in neuropathic pain rats with L5 spinal nerve ligation

Qing-Ying Liu; Wen Chen; Shuang Cui; Fei-Fei Liao; Ming Yi; Feng-Yu Liu; You Wan

doi:10.1016/j.neures.2018.04.002

Upregulation of Ca_v3.2 T-type calcium channels in adjacent intact L4 dorsal root ganglion neurons in neuropathic pain rats with L5 spinal nerve ligation

Neurosci Res. 2019 May:142:30-37. doi: 10.1016/j.neures.2018.04.002. Epub 2018 Apr 21.

Authors

Qing-Ying Liu¹, Wen Chen¹, Shuang Cui², Fei-Fei Liao², Ming Yi², Feng-Yu Liu³, You Wan⁴

Affiliations

¹ Neuroscience Research Institute, Peking University, Beijing 100083, China; Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing 100083, China; Key Laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing 100083, China.
² Neuroscience Research Institute, Peking University, Beijing 100083, China.
³ Neuroscience Research Institute, Peking University, Beijing 100083, China; Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing 100083, China. Electronic address: liufyu@bjmu.edu.cn.
⁴ Neuroscience Research Institute, Peking University, Beijing 100083, China; Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing 100083, China; Key Laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing 100083, China. Electronic address: ywan@hsc.pku.edu.cn.

PMID: 29684385
DOI: 10.1016/j.neures.2018.04.002

Abstract

Besides the injured peripheral dorsal root ganglion (DRG) neurons, the adjacent intact DRG neurons also have important roles in neuropathic pain. Ion channels including Ca_v3.2 T-type calcium channel in the DRG neurons are important in the development of neuropathic pain. In the present study, we aimed to examine the expression of Ca_v3.2 T-type calcium channels in the intact DRG neurons in neuropathic pain. A neuropathic pain model of rat with lumbar 5 (L5) spinal nerve ligation (SNL) was established, in which the L4 DRG was separated from the axotomized L5 DRG, and the molecular, morphological and electrophysiological changes of Ca_v3.2 T-type calcium channels in L4 DRG neurons were investigated. Western blotting showed that total and membrane protein levels of Ca_v3.2 in L4 DRG neurons increased, and voltage-dependent patch clamp recordings revealed an increased T-type current density with a curve shift to the left in steady-state activation in the acutely isolated L4 DRG neurons in neuropathic pain rats. Immunofluorescent staining further showed that the membrane expression of Ca_v3.2 increased in CGRP-, IB4-positive small neurons and NF200-positive large ones. In conclusion, the membrane expression and the function of Ca_v3.2 T-type calcium channels are increased in the intact L4 DRG neurons in neuropathic pain rats with peripheral nerve injury like SNL.

Keywords: Ca(v)3.2 T-type calcium channel; Dorsal root ganglion; Neuropathic pain; Spinal nerve ligation.

MeSH terms

Animals
Calcium Channels, T-Type / metabolism*
Ganglia, Spinal / metabolism*
Hyperalgesia / etiology
Hyperalgesia / metabolism
Ligation
Lumbar Vertebrae
Lumbosacral Region
Male
Neuralgia / complications
Neuralgia / metabolism*
Neurons / metabolism*
Peripheral Nerve Injuries / complications
Peripheral Nerve Injuries / metabolism*
Rats, Sprague-Dawley
Up-Regulation

Substances

Cacna1h protein, rat
Calcium Channels, T-Type