title: Effect of 835 MHz radiofrequency radiation exposure on calcium binding proteins in the hippocampus of the mouse brain.
abstract: Worldwide expansion of mobile phones and electromagnetic field (EMF) exposure has raised question of their possible biological effects on the brain and nervous system. Radiofrequency (RF) radiation might alter intracellular signaling pathways through changes in calcium (Ca(2+)) permeability across cell membranes. Changes in the expression of calcium binding proteins (CaBP) like calbindin D28-k (CB) and calretinin (CR) could indicate impaired Ca(2+)homeostasis due to EMF exposure. CB and CR expression were measured with immunohistochemistry in the hippocampus of mice after EMF exposure at 835 MHz for different exposure times and absorption rates, 1 h/day for 5 days at a specific absorption rate (SAR)=1.6 W/kg, 1 h/day for 5 days at SAR=4.0 W/kg, 5 h/day for 1 day at SAR=1.6 W/kg, 5 h/day for 1 day at SAR=4.0 W/kg, daily exposure for 1 month at SAR=1.6 W/kg. Body weights did not change significantly. CB immunoreactivity (IR) displayed moderate staining of cells in the cornu ammonis (CA) areas and prominently stained granule cells. CR IR revealed prominently stained pyramidal cells with dendrites running perpendicularly in the CA area. Exposure for 1 month produced almost complete loss of pyramidal cells in the CA1 area. CaBP differences could cause changes in cellular Ca(2+)levels, which could have deleterious effect on normal hippocampal functions concerned with neuronal connectivity and integration.
authors.affiliation: Department of Anatomy, Dankook University College of Medicine, Cheonan-si, San 29, Anseo-Dong, Cheonan, Chungnam, South Korea.
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Maskey
authors.forename: Minsoo
authors.initials: M
authors.lastname: Kim
authors.forename: Bijay
authors.initials: B
authors.lastname: Aryal
authors.forename: Jonu
authors.initials: J
authors.lastname: Pradhan
authors.forename: In-Young
authors.initials: IY
authors.lastname: Choi
authors.forename: Ki-Sup
authors.initials: KS
authors.lastname: Park
authors.forename: Taeho
authors.initials: T
authors.lastname: Son
authors.forename: Sae-Yong
authors.initials: SY
authors.lastname: Hong
authors.forename: Seok Bae
authors.initials: SB
authors.lastname: Kim
authors.forename: Hyung Gun
authors.initials: HG
authors.lastname: Kim
authors.forename: Myeung Ju
authors.initials: MJ
authors.lastname: Kim
mesh_terms: D000042:Absorption; D000818:Animals; D001835:Body Weight / Q000528:radiation effects; D056547:CA1 Region, Hippocampal / Q000502:physiology / Q000528:radiation effects; D064032:Calbindin 2; D064026:Calbindins; D002452:Cell Count; D004574:Electromagnetic Fields / Q000009:adverse effects; D006624:Hippocampus / Q000502:physiology / Q000528:radiation effects*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009474:Neurons / Q000502:physiology / Q000528:radiation effects*; D010784:Photomicrography; D017966:Pyramidal Cells / Q000502:physiology / Q000528:radiation effects; D011829:Radiation Dosage; D011846:Radio Waves / Q000009:adverse effects*; D064030:S100 Calcium Binding Protein G / Q000378:metabolism*; D013997:Time Factors
chemical_list: C576511:Calb2 protein, mouse; D064032:Calbindin 2; D064026:Calbindins; D064030:S100 Calcium Binding Protein G