[Study of histometric and histopathologic changes and biochemical functioning of liver in mice Balb/C treated with methylphenidate]

Background: Methylphenidate or ritalin is one of the brain stimulant drug and used in treatment of attention deficit hyperactivity disorder [ADHD], narcolepsy and situational tachycardia syndrome. In the present survey, the effect of methylphenidate on the liver was studied

Materials and methods: In this experimental study, a total of 24 male mice were randomly divided into three groups, including one control and two experimental groups. In experimental groups, Ritalin was used in the doses of 2 and 10 mg/kg by gavages method for 40 days. At the end of the period and after animals' euthanasia, the livers specimens were removed. Then, histological changes were studied using a light microscope. Also, blood sera were collected and the hepatic enzymes activity was determined. The data were statistically analyzed by ANOVA test and the p<0.05 was considered as significant

Results: Administration of methylphenidate in different concentrations resulted in significant reduction of hepatocytes diameters, decrease in nuclei diameters, increase in the size of hepatic sinusoids, and also necrosis and congestion in central vein. Furthermore, in the liver parenchyma belonging to treated groups, the infiltration of mononuclear leukocytes was observed. In the treated groups, the activity of the hepatic enzymes showed a significant increase compared with the control group

Conclusion: Considering the present findings, it could be suggested to avoid of prescribing of methylphenidate, especially in the patients with hepatic failures

Histological, histometrical and thyroid hormones serum level evaluation after chronic nicotine exposure in mice

Nicotine is an ingredient of cigarette smoke that has a lot of psychological and physical effects on addicted persons. The aim of this study was to evaluate nicotine effects on functional and histological alteration in thyroid gland that has important role on metabolic activities. In this experimental study, 40 mature male mice [25-30 gr] were divided to one control group and 3 experimental groups that received nicotine with dosage of 100, 200 and 400 micro g/kg via oral gavage once a day for 60 days. Then, T[3], T[4] and TSH serum levels were measured and histomorphometric evaluation of thyroid gland was done. Significant decrease in body weight and thyroid follicular epithelial height and significant increase in serum level of T[3] were noted. This study showed that nicotine can cause alteration on metabolic activities of thyroid gland via the increase of T[3] serum level and the decrease of follicular epithelial height

Role of fibrocytes [CD34+] derived from peripheral blood in the pathology of dermal fibrosis in a model of scleroderma

Peripheral blood fibrocytes are a newly identified circulating leukocyte subpopulation that migrates into injured tissue where it may display fibroblast-like properties and participate in wound healing and fibrosis of skin and other organs. In this study, fibrocyte recruitment to skin in a bleomycin-induced dermal fibrosis model of human scleroderma in vivo was studied. Sections of skin from normal mice [control group] and bleomycin-treated C57BL/6 mice [Experimental group] were stained for Procollagen a2 Type I and CD34 and the double stained cells, and also fibrocytes were counted in the tissue sections. There were more fibrocytes in the dermis of experimental group than control group. There was no significant difference in fibrocyte number between skin samples with 1 week bleomycin treated and 3 weeks treated samples. We also found that fibrocytes [CD34+ and procollagen+] were mainly localized in clusters around blood vessels in the dermis and also individually close to epithelium. Our data suggest an important role of fibrocytes in the pathology of dermal fibrosis