The Effect of Oral Administration of Methylphenidate on Hippocampal Tissue in Adult Male Rats

Abstract

Introduction:Methylphenidate is a central nervous system stimulant drug that has become the primary drug of choice in treating attention-deficit/hyperactivity disorder in children. The aim of the present study was to investigate the short-term effect of oral administration of methylphenidate hydrochloride on the hippocampal tissue in adult rats. Methods:Twenty-eight male Wistar rats were divided to 4 groups (N=7): vehicle group, received distilled water; control groups, received no treatment; 2 experimental groups: received methylphenidate hydrochloride (3 and 10 mg/kg dissolved in distilled water) orally once daily for 6 days. On sixth day all rats were anesthetized and to study the tissue changes in hippocampus area of rats, tissue sections were prepared after a month and stained with hematoxylin-eosin staining. Results:In dose 3 mg, a dense cytoplasm and nucleus in cornus ammonis 3, 4 and dentate gyrus neurons of hippocampus were observed. The dose 10 mg, in addition to mentioned areas, caused necrosis in cornus ammonis 1 and 2 areas of hippocampus. In addition to the morphometric analysis indicated that the number of necrotic hippocampal cells in cornus ammonis and dentate gyrus areas was significantly increased in rats receiving methylphenidate. Conclusions:Our findings suggested that oral administration of methylphenidate hydrochloride can induce hippocampal necrosis in adult rats.