title: Rearing in an enriched environment attenuated hyperactivity and inattention in the Spontaneously Hypertensive Rats, an animal model of Attention-Deficit Hyperactivity Disorder.
abstract: Attention-deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder, characterized by symptoms of hyperactivity, inattention, and impulsivity. It is commonly treated with psychostimulants that typically begins during childhood and lasts for an extended period of time. However, there are concerns regarding the consequences of chronic psychostimulant treatment; thus, there is a growing search for an alternative management for ADHD. One non-pharmacological management that is gaining much interest is environmental enrichment. Here, we investigated the effects of rearing in an enriched environment (EE) on the expression of ADHD-like symptoms in the Spontaneously Hypertensive Rats (SHRs), an animal model of ADHD. SHRs were reared in EE or standard environment (SE) from post-natal day (PND) 21 until PND 49. Thereafter, behavioral tests that measure hyperactivity (open field test [OFT]), inattention (Y-maze task), and impulsivity (delay discounting task) were conducted. Additionally, electroencephalography (EEG) was employed to assess the effects of EE on rat's brain activity. Wistar-Kyoto (WKY) rats, the normotensive counterpart of the SHRs, were used to determine whether the effects of EE were specific to a particular genetic background. EE improved the performance of the SHRs and WKY rats in the OFT and Y-maze task, but not the delay discounting task. Interestingly, EE induced significant EEG changes in WKY rats, but not in the SHRs. These findings show that rearing environment may play a role in the expression of ADHD-like symptoms in the SHRs and that EE may be considered as a putative complementary approach in managing ADHD symptoms.
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: Chrislean Jun
authors.initials: CJ
authors.lastname: Botanas
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: Hyelim
authors.initials: H
authors.lastname: Lee
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: June Bryan
authors.initials: JB
authors.lastname: de la Peña
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: Irene Joy
authors.initials: IJ
authors.lastname: Dela Peña
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: Taeseon
authors.initials: T
authors.lastname: Woo
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Psychiatry, Chung-Ang University Medical School, 102 Heukseok-ro, Dongjak-gu, Seoul 156-755, Republic of Korea.
authors.forename: Doug Hyun
authors.initials: DH
authors.lastname: Han
authors.affiliation: Division of Child and Adolescent Psychiatry, Clinical Research Institute, Seoul National University Hospital, 28 Yungundong, Chongrogu, Seoul 110-744, Republic of Korea.
authors.forename: Bung-Nyun
authors.initials: BN
authors.lastname: Kim
authors.affiliation: Uimyung Research Institute for Neuroscience, School of Pharmacy, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815 Nowon-gu, Seoul 139-742, Republic of Korea. Electronic address: cheongjh@syu.ac.kr.
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Cheong
mesh_terms: D000818:Animals; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology* / Q000628:therapy*; D001921:Brain / Q000503:physiopathology*; D015331:Cohort Studies; D065786:Delay Discounting / Q000502:physiology; D004195:Disease Models, Animal; D000069280:Electrocorticography; D004777:Environment; D006799:Housing, Animal; D008297:Male; D018782:Maze Learning / Q000502:physiology; D009043:Motor Activity / Q000502:physiology*; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
keywords: Attention deficit hyperactivity disorder; Environmental enrichment; Spontaneously Hypertensive Rats; Wistar-Kyoto rats