title: Effects of repeated 9 and 30-day exposure to extremely low-frequency electromagnetic fields on social recognition behavior and estrogen receptors expression in olfactory bulb of Wistar female rats.
abstract: OBJECTIVE
  We investigated the short- and long-term effects of extremely low-frequency electromagnetic fields (EMF) on social recognition behavior and expression of α- and β-estrogen receptors (ER).
  
  
  METHODS
  Rats were exposed to 60-Hz electromagnetic fields for 9 or 30 days and tested for social recognition behavior. Immunohistochemistry and western blot assays were performed to evaluate α- and β-ER expression in the olfactory bulb of intact, ovariectomized (OVX), and ovariectomized+estradiol (E2) replacement (OVX+E2).
  
  
  RESULTS
  Ovariectomization showed impairment of social recognition after 9 days of EMF exposure and a complete recovery after E2 replacement and so did those after 30 days. Short EMF exposure increased expression of β-ER in intact, but not in the others. Longer exposure produced a decrease in intact but an increase in OVX and OVX+E2.
  
  
  CONCLUSIONS
  Our findings suggest a significant role for β-estrogen receptors and a lack of effect for α-estrogen receptors on a social recognition task.
  
  
  BACKGROUND
  EMF: extremely low frequency electromagnetic fields; ERs: estrogen receptors; OB: olfactory bulb; OVX: ovariectomized; OVX + E2: ovariectomized + estradiol replacement; IEI: interexposure interval; β-ER: beta estrogen receptor; E2: replacement of estradiol; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; WB: Western blot; PBS: phosphate-buffer saline; PB: phosphate-buffer.
authors.affiliation: a Facultad de Medicina, Departamento de Fisiología , Universidad Nacional Autónoma de México , Ciudad de México , Mexico.
authors.forename: C
authors.initials: C
authors.lastname: Bernal-Mondragón
authors.affiliation: a Facultad de Medicina, Departamento de Fisiología , Universidad Nacional Autónoma de México , Ciudad de México , Mexico.
authors.forename: V
authors.initials: V
authors.lastname: Arriaga-Avila
authors.affiliation: b División Académica Multidisciplinaria de Comalcalco , Universidad Juárez Autónoma de Tabasco , Comalcalco , Mexico.
authors.forename: E
authors.initials: E
authors.lastname: Martínez-Abundis
authors.affiliation: a Facultad de Medicina, Departamento de Fisiología , Universidad Nacional Autónoma de México , Ciudad de México , Mexico.
authors.forename: B
authors.initials: B
authors.lastname: Barrera-Mera
authors.affiliation: a Facultad de Medicina, Departamento de Fisiología , Universidad Nacional Autónoma de México , Ciudad de México , Mexico.
authors.forename: O
authors.initials: O
authors.lastname: Mercado-Gómez
authors.affiliation: a Facultad de Medicina, Departamento de Fisiología , Universidad Nacional Autónoma de México , Ciudad de México , Mexico.
authors.forename: R
authors.initials: R
authors.lastname: Guevara-Guzmán
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D004195:Disease Models, Animal; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects / Q000528:radiation effects; D008124:Locomotion / Q000187:drug effects / Q000528:radiation effects; D009830:Olfactory Bulb / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D011960:Receptors, Estrogen / Q000378:metabolism*; D021641:Recognition, Psychology / Q000187:drug effects / Q000528:radiation effects*; D012919:Social Behavior; D013997:Time Factors
chemical_list: D011960:Receptors, Estrogen; D004958:Estradiol
keywords: EMF; Social recognition memory; olfactory bulb; α-estrogen receptors; β-estrogen receptors