Ryanodine Receptor-mediated Calcium Release Regulates Neuronal Excitability in Rat Spinal Substantia Gelatinosa Neurons.
10.11620/IJOB.2015.40.4.211
- Author:
Areum PARK
1
;
Sang Woo CHUN
Author Information
1. Department of Oral Physiology, College of Dentistry, Institute of Wonkwang Biomaterial and Implant, Wonkwang University, Iksan 570-749, Korea. physio1@wonkwang.ac.kr
- Publication Type:Original Article
- Keywords:
substantia gelatinosa neuron;
nitric oxide;
calcium release;
ryanodine receptor;
patch clamp
- MeSH:
Animals;
Calcium*;
Charybdotoxin;
Endoplasmic Reticulum;
Humans;
Membranes;
Neurons*;
Nitric Oxide;
Nitroprusside;
Potassium;
Rats*;
Ryanodine Receptor Calcium Release Channel;
Ryanodine*;
Substantia Gelatinosa*;
Thapsigargin;
Tissue Donors
- From:International Journal of Oral Biology
2015;40(4):211-216
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Nitric Oxide (NO) is an important signaling molecule in the nociceptive process. Our previous study suggested that high concentrations of sodium nitroprusside (SNP), a NO donor, induce a membrane hyperpolarization and outward current through large conductances calcium-activated potassium (BKca) channels in substantia gelatinosa (SG) neurons. In this study, patch clamp recording in spinal slices was used to investigate the sources of Ca2+ that induces Ca2+-activated potassium currents. Application of SNP induced a membrane hyperpolarization, which was significantly inhibited by hemoglobin and 2-(4-carboxyphenyl) -4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO), NO scavengers. SNP-induced hyperpolarization was decreased in the presence of charybdotoxin, a selective BKCa channel blocker. In addition, SNP-induced response was significantly blocked by pretreatment of thapsigargin which can remove Ca2+ in endoplasmic reticulum, and decreased by pretreatment of dentrolene, a ryanodine receptors (RyR) blocker. These data suggested that NO induces a membrane hyperpolarization through BKca channels, which are activated by intracellular Ca2+ increase via activation of RyR of Ca2+ stores.
