Effects of moderate static magnetic fields on the voltage-gated sodium and calcium channel currents in trigeminal ganglion neurons. (2nd October 2015)

• Record Type: Journal Article
• Authors: Lu, Xiao-Wen; Du, Li; Kou, Liang; Song, Ning; Zhang, Yu-Jiao; Wu, Min-Ke; Shen, Jie-Fei
• Is Part Of: Electromagnetic biology and medicine. Volume 34:Number 4(2015:Oct.)
• Page Start: 285
• Page End: 292
• Publication Date: 2015-10-02
• Subjects: 125-mT -- 12.5-mT -- calcium channel -- static magnetic fields -- sodium channel -- trigeminal ganglion neuron -- whole-cell patch-clamp; Electrophysiology -- Periodicals; Electromagnetic Fields -- Periodicals; Electrophysiology -- Periodicals; Radiation, Nonionizing -- Periodicals; 574
• DOI: 10.3109/15368378.2014.906448
• Languages: English
• ISSNs: 1536-8378

Abstract

Abstract: Aim : To study the effects of static magnetic fields (SMF) on the electrophysiological properties of voltage-gated sodium and calcium channels on trigeminal ganglion (TRG) neurons. Methods : Acutely dissociated TRG neurons of neonatal SD rats were exposed to 125-mT and 12.5-mT SMF in exposure devices and whole-cell patch-clamp recordings were carried out to observe the changes of voltage-gated sodium channels (VGSC) and calcium channels (VGCC) currents, while laser scanning confocal microscopy was used to detect intracellular free Ca 2+ concentration in TRG neurons, respectively. Results : (1) No obvious change of current–voltage (I–V) relationship and the peak current densities of VGSC and VGCC currents were found when TRG neurons were exposed to 125-mT and 12.5-mT SMF. However, the activation threshold, inactivation threshold and velocity of the channel currents above were significantly altered by 125-mT and 12.5-mT SMF. (2) The fluctuation of intracellular free Ca 2+ concentration within TRG neurons were slowed by 125-mT and 12.5-mT SMF. When SMF was removed, the Ca 2+ concentration level showed partial recovery in the TRG neurons previously exposed by 125-mT SMF, while there was a full recovery found in 12.5-mT-SMF-exposed neurons. Conclusions : Moderate-intensity SMF could affect the electrophysiological characteristics of VGCS and VGCC by altering their activation and inactivation threshold and velocity. The fluctuations of intracellular free Ca 2+ caused by SMF exposure were not permanent in TRG neurons.