Oral Administration of Methylphenidate Induces Hippocampal Necrosis in Juvenile Rats

Abstract

Introduction: Methylphenidate (MPH: Ritalin) is a neural stimulant prescribed for the treatment of attention-deficit/hyperactivity disorder. The recent neurochemical studies indicated that repeated administration of MPH to juvenile rats attenuated hippocampal neurogenesis in adulthood. The aim of the present study was to investigate the effect of oral administration of MPH on the hippocampal tissue in juvenile rats. Methods: A total of 28 juvenile male Wistar rats were divided into 4 groups (N=7): 2 experimental, 1 vehicle, and 1 control group. Animals in the experimental groups received MPH (3 and 10 mg/kg dissolved in distilled water) orally once daily during preadolescence (postnatal days 26 to 40). In the vehicle group, animals received distilled water, and the animals in the control group received no treatment. To study the tissue changes in the hippocampus area of rats, tissue sections were prepared after a month and stained with hematoxylin-eosin and periodic acid-Schiff staining. Results: The results indicated that the 3 mg dose induced necrosis in the hippocampal cornu ammonis (CA 1, CA 2, and CA 3) areas. The 10 mg dose, in addition to the above-mentioned areas, caused necrosis in the dentate gyrus area of the hippocampus. Conclusion: These findings suggested that oral administration of MPH can induce hippocampal necrosis in juvenile rats. © 2014 Wolters Kluwer Health, Inc. All rights reserved.