Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats
The diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) often results in chronic treatment with psychostimulants such as methylphenidate (MPH, Ritalin®). With increases in misdiagnosis of ADHD, children may be inappropriately exposed to chronic psychostimulant treatment during development....
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MDPI AG
2012-09-01
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| Series: | Brain Sciences |
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| Online Access: | http://www.mdpi.com/2076-3425/2/3/375 |
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| author | Jennifer L. Cornish Judi Homewood Kelly J. Clemens Ann K. Goodchild Natasha N. Kumar Margery C. Pardey |
| author_facet | Jennifer L. Cornish Judi Homewood Kelly J. Clemens Ann K. Goodchild Natasha N. Kumar Margery C. Pardey |
| author_sort | Jennifer L. Cornish |
| collection | DOAJ |
| description | The diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) often results in chronic treatment with psychostimulants such as methylphenidate (MPH, Ritalin®). With increases in misdiagnosis of ADHD, children may be inappropriately exposed to chronic psychostimulant treatment during development. The aim of this study was to assess the effect of chronic Ritalin treatment on cognitive and neural development in misdiagnosed “normal” (Wistar Kyoto, WKY) rats and in Spontaneously Hypertensive Rats (SHR), a model of ADHD. Adolescent male animals were treated for four weeks with oral Ritalin® (2 × 2 mg/kg/day) or distilled water (dH2O). The effect of chronic treatment on delayed reinforcement tasks (DRT) and tyrosine hydroxylase immunoreactivity (TH-ir) in the prefrontal cortex was assessed. Two weeks following chronic treatment, WKY rats previously exposed to MPH chose the delayed reinforcer significantly less than the dH2O treated controls in both the DRT and extinction task. MPH treatment did not significantly alter cognitive performance in the SHR. TH-ir in the infralimbic cortex was significantly altered by age and behavioural experience in WKY and SHR, however this effect was not evident in WKY rats treated with MPH. These results suggest that chronic treatment with MPH throughout adolescence in “normal” WKY rats increased impulsive choice and altered catecholamine development when compared to vehicle controls. |
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| institution | Directory Open Access Journal |
| issn | 2076-3425 |
| language | English |
| last_indexed | 2024-12-22T01:12:17Z |
| publishDate | 2012-09-01 |
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| record_format | Article |
| series | Brain Sciences |
| spelling | doaj.art-67eefd83519f42e495b42fa297daac7f2022-12-21T18:43:57ZengMDPI AGBrain Sciences2076-34252012-09-012337540410.3390/brainsci2030375Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto RatsJennifer L. CornishJudi HomewoodKelly J. ClemensAnn K. GoodchildNatasha N. KumarMargery C. PardeyThe diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) often results in chronic treatment with psychostimulants such as methylphenidate (MPH, Ritalin®). With increases in misdiagnosis of ADHD, children may be inappropriately exposed to chronic psychostimulant treatment during development. The aim of this study was to assess the effect of chronic Ritalin treatment on cognitive and neural development in misdiagnosed “normal” (Wistar Kyoto, WKY) rats and in Spontaneously Hypertensive Rats (SHR), a model of ADHD. Adolescent male animals were treated for four weeks with oral Ritalin® (2 × 2 mg/kg/day) or distilled water (dH2O). The effect of chronic treatment on delayed reinforcement tasks (DRT) and tyrosine hydroxylase immunoreactivity (TH-ir) in the prefrontal cortex was assessed. Two weeks following chronic treatment, WKY rats previously exposed to MPH chose the delayed reinforcer significantly less than the dH2O treated controls in both the DRT and extinction task. MPH treatment did not significantly alter cognitive performance in the SHR. TH-ir in the infralimbic cortex was significantly altered by age and behavioural experience in WKY and SHR, however this effect was not evident in WKY rats treated with MPH. These results suggest that chronic treatment with MPH throughout adolescence in “normal” WKY rats increased impulsive choice and altered catecholamine development when compared to vehicle controls.http://www.mdpi.com/2076-3425/2/3/375methylphenidateadolescenttyrosine hydroxylasechronic administrationprefrontal corteximpulsivityimpulsive choice |
| spellingShingle | Jennifer L. Cornish Judi Homewood Kelly J. Clemens Ann K. Goodchild Natasha N. Kumar Margery C. Pardey Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats Brain Sciences methylphenidate adolescent tyrosine hydroxylase chronic administration prefrontal cortex impulsivity impulsive choice |
| title | Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats |
| title_full | Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats |
| title_fullStr | Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats |
| title_full_unstemmed | Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats |
| title_short | Long-Term Effects of Chronic Oral Ritalin Administration on Cognitive and Neural Development in Adolescent Wistar Kyoto Rats |
| title_sort | long term effects of chronic oral ritalin administration on cognitive and neural development in adolescent wistar kyoto rats |
| topic | methylphenidate adolescent tyrosine hydroxylase chronic administration prefrontal cortex impulsivity impulsive choice |
| url | http://www.mdpi.com/2076-3425/2/3/375 |
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