Effects of acrylonitrile in drinking water on monoamine neurotransmitters and its metabolites in male rat brains

Objectives To elucidate the p ossible involvement of monoamine neurotransmitters in the development of neurobe havioral damage produced by acrylonitrile in drinking water in male rat brains. Methods Totally 30 male SD rats were randomly divided int o three groups, the control group (n=10), low dosage group (n=10), and h igh dosage group (n=10), which were respectively administered 0 mg/L, 50 mg/L, 200 mg/L acrylonitrile (AN) in drinking water.The treatment was lasted for 12 weeks.Seven animals were randomly selected from each group for determin ation of monoamine neurotransmitters in striatum and cerebellum by high performa nce liquid chromatography with electrochemical detector and activities of monoam ine oxidase in cortex.Results The contents of dopamine i n the striatum of low and high dosage groups were decreased to (2.2±0.7) and (3.2±2.0) μg/g wet tissue, resepetively, and compared with that of control g roup (9.0±4.2) μg/g wet tissue, the differences were statistically significa nt.There were no statistical differences among the contents of dopamine in the cerebellum of all rats, and the levels of 3,4-dihydroxyphenylacetic acid (DOPAC ), the major metabolite of dopamine in the cerebellum were (186±41), (245±90) and (115±65) ng/g wet tissue in the control, low and high dosage groups, respec tively and in low-dosage group they were significantly higher than those in oth er groups.There was dosage-dependently decreasing of the cont ents of serotonin of striatum in the control (249±34) ng/g wet tissue, low dosa ge (155±95) ng/g wet tissue and high dosage groups (128±101) ng/g wet tissue. Conclusion This study underlines the importance of alter ations in the monoamine neurotransmitters system as a possible causative mechani sm behind the behavioural and functional changes produced by acrylonitrile .