effects of methylphenidate on the mice adrenal glands and lymphoid organs: results of histochemical, histometrical and histopathological investigations

Background: considering the wide administration of methylphenidate and also its immunosuppressive effects on different organs, the importance of related microscopic studies is obvious. objectives: determining histological effects of methylphenidate on adrenal glands and lymphatic organs in mice. methods: a total number of 30 adult male balb/c mice were provided, weighed and divided into one control and two experimental groups. the control group received water by gavages once a day, for 40 days. the experimental groups were orally administered mph hydrochloride (2mg/kg and 10mg/kg body weight,) respectively. animals were anesthetized and blood samples were collected through cardiac puncture for analysis of blood cells. spleen, thymus, lymph nodes and adrenal glands were removed and processed for microscopic studies through hematoxylin and eosin staining. spleen samples were processed for plasma cell count and staining (label antibody cd138*). the data were analyzed using analysis of variance (anova) and p<0.05 was considered significant. results: the changes in lymphoid organs provided morphological evidence for mph induced immune suppression. our findings showed increase in the number of megakaryocytes in spleen, neutrophils of peripheral blood and thickness in capsule of thymus and lymph node. also, thickening of the adrenal cortex and medulla, decrease in the reticularis layer of adrenal cortex and medulla of thymus and decreasing lymphocytes in peripheral blood were significantly observed in experimental groups. moreover, there were significant changes in serum cortisol. conclusions: regarding the resulted data indicating some pathologic, inhibitory and suppressive roles of methylphenidate on immune system and the studied organs, it is suggested that caution should be considered in prescription of this medication.