Counteraction by repetitive daily exposure to static magnetism against sustained blockade of N-methyl-D-aspartate receptor channels in cultured rat hippocampal neurons

Takao Hirai; Hideo Taniura; Yasuaki Goto; Keisuke Tamaki; Hirotaka Oikawa; Yuki Kambe; Masato Ogura; Yu Ohno; Takeshi Takarada; Yukio Yoneda

doi:10.1002/jnr.20497

Counteraction by repetitive daily exposure to static magnetism against sustained blockade of N-methyl-D-aspartate receptor channels in cultured rat hippocampal neurons

J Neurosci Res. 2005 May 15;80(4):491-500. doi: 10.1002/jnr.20497.

Authors

Takao Hirai¹, Hideo Taniura, Yasuaki Goto, Keisuke Tamaki, Hirotaka Oikawa, Yuki Kambe, Masato Ogura, Yu Ohno, Takeshi Takarada, Yukio Yoneda

Affiliation

¹ Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School of Natural Science and Technology, Kakuma-machi, Kanazawa, Ishikawa, Japan.

PMID: 15846781
DOI: 10.1002/jnr.20497

Abstract

In rat hippocampal neurons cultured with the antagonist for N-methyl-D-aspartate (NMDA) receptors dizocilpine (MK-801) for 8 days in vitro (DIV), a significant decrease was seen in the expression of microtubule-associated protein-2 (MAP-2) as well as mRNA for both brain-derived neurotrophic factor (BDNF) and growth-associated protein-43 (GAP-43), in addition to decreased viability. MK-801 not only decreased the expression of the NR1 subunit of NMDA receptors but also increased NR2A expression, without affecting NR2B expression. Repetitive daily exposure to static magnetic fields at 100 mT for 15 min led to a decrease in the expression of MAP-2, without significantly affecting cell viability or the expression of neuronal nuclei (NeuN) and GAP-43. However, the repetitive magnetism prevented decreases in both BDNF mRNA and MAP-2 and additionally increased the expression of NR2A subunit, without altering NR1 expression in neurons cultured in the presence of MK-801. Repetitive magnetism was also effective in preventing the decrease by MK-801 in the ability of NMDA to increase intracellular free Ca2+ ions, without affecting the decrease in the maximal response. These results suggest that repetitive magnetism may at least in part counteract the neurotoxicity of MK-801 through modulation of the expression of particular NMDA receptor subunits in cultured rat hippocampal neurons.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Analysis of Variance
Animals
Blotting, Western / methods
Brain-Derived Neurotrophic Factor / genetics
Brain-Derived Neurotrophic Factor / metabolism
Calcium / metabolism
Cell Survival / drug effects
Cell Survival / radiation effects
Cells, Cultured
Dizocilpine Maleate / pharmacology*
Dose-Response Relationship, Drug
Embryo, Mammalian
Excitatory Amino Acid Antagonists / pharmacology*
Extracellular Space / drug effects
Extracellular Space / metabolism
Extracellular Space / radiation effects
GAP-43 Protein / genetics
GAP-43 Protein / metabolism
Gene Expression Regulation / drug effects
Gene Expression Regulation / physiology
Gene Expression Regulation / radiation effects
Hippocampus / cytology*
Magnetics*
Microtubule-Associated Proteins / genetics
Microtubule-Associated Proteins / metabolism
N-Methylaspartate / pharmacology
Neurons / drug effects*
Neurons / metabolism
Neurons / radiation effects*
Phosphopyruvate Hydratase / metabolism
RNA, Messenger / metabolism
Rats
Rats, Wistar
Receptors, N-Methyl-D-Aspartate / genetics
Receptors, N-Methyl-D-Aspartate / metabolism
Reverse Transcriptase Polymerase Chain Reaction / methods
Time Factors

Substances

Brain-Derived Neurotrophic Factor
Excitatory Amino Acid Antagonists
GAP-43 Protein
Microtubule-Associated Proteins
RNA, Messenger
Receptors, N-Methyl-D-Aspartate
N-Methylaspartate
Dizocilpine Maleate
Phosphopyruvate Hydratase
Calcium
N-methyl D-aspartate receptor subtype 2A