Magnetic, but not non-magnetic, reduced graphene oxide in spinal cord increases nociceptive neuronal responsiveness.
The interference between external magnetic fields and neurophysiology is not new, however, the role of the neuronal magnetic field remains unclear. This study aimed at investigating a possible role of the neuronal magnetic field in nociception. Highly and poorly magnetic reduced graphene oxide (rGO) was injected intrathecally in rats. Nociceptive responsiveness was greater in rats that received highly magnetic-rGO in von Frey electronic or intraplantar capsaicin tests. Furthermore, in vitro experiments demonstrated that the number of KCl-responsive DRG-neurons was greater when treated with highly magnetic-rGO when compared with non-magnetic-rGO. Our data also suggested that the mechanism underlying the increased nociceptive responsiveness involves increased Ca2+vactivity. Complementary experiments excluded the cytotoxic and inflammatory effects of the magnetic-rGO in neuronal responsiveness. These data suggest that the disturbance of the neuronal magnetic field in spinal cord increases nociceptive responsiveness, suggesting an importance of the magnetic component of the electromagnetic field in neuronal transmission.
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil. Electronic address: luispmanzo@yahoo.com.br.
Luis Paulo
LP
Manzo
Department of semiconductors, Instruments and Photonics, School of Electrical and Computer Engineering, State University of Campinas.
Helder
H
Ceragioli
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil.
Ivan José
IJ
Bonet
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil.
Catarine Massucato
CM
Nishijima
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil.
Willians Fernando
WF
Vieira
Technology Faculty of Sorocaba - Paula Souza State Center of Technological Education, Sorocaba, SP, Brazil.
Elaine Conceição
EC
Oliveira
School of Electrical Engineering - FEELT and School of Medicine, LMCETC/FAMED, Federal University of Uberlandia, UFU, Uberlandia, Minas Gerais, Brazil.
João-Batista
JB
Destro-Filho
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil.
César Renato
CR
Sartori
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil.
Claudia Herrera
CH
Tambeli
Department of structural and functional biology, Biology Institute - State University of Campinas, Campinas, SP, Brazil. Electronic address: caparada@unicamp.br.
Carlos Amilcar
CA
Parada
D000818:Animals; D006108:Graphite; D060526:Magnetic Fields; D009619:Nociceptors; D010087:Oxides; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*
D010087:Oxides; D006108:Graphite
Ephaptic transmission; Neuronal magnetic field; Neuronal responsiveness; Reduced graphene oxide