title: Effects of extremely low-frequency electromagnetic fields on morphine-induced conditioned place preferences in rats.
abstract: In the present study, we examined the effects of extremely low-frequency (ELF) electromagnetic fields on morphine-induced conditioned place preferences in rats. During the conditioning phase (12 days), three groups of rats were placed in a sensory cue-defined environment paired with morphine (10mg/kg, i.p.) following exposure to either 20 Hz (1.80 mT) or 50 Hz (2.20 mT) or sham electromagnetic fields for 60 min/day, respectively, and were placed in another sensory cue-defined environment paired with physiological saline (1 ml/kg, i.p.) without exposure to electromagnetic fields. After finishing 12 days of conditioning, preference tests for the morphine-paired place were performed during a 10-day withdrawal period. The exposure to electromagnetic fields substantially potentiated morphine-induced place preferences in rodents, suggesting that ELF electromagnetic fields can increase the propensity for morphine-induced conditioned behaviors.
authors.affiliation: Laboratory of Cognitive Brain Research, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, PR China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Lei
authors.forename: Tianyue
authors.initials: T
authors.lastname: Liu
authors.forename: Fraser A W
authors.initials: FA
authors.lastname: Wilson
authors.forename: Dongming
authors.initials: D
authors.lastname: Zhou
authors.forename: Yuanye
authors.initials: Y
authors.lastname: Ma
authors.forename: Xintian
authors.initials: X
authors.lastname: Hu
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D003213:Conditioning, Psychological / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D004574:Electromagnetic Fields; D006801:Humans; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine