Effects of pyrethroids on dopamine and its metabolites in nigrostriatum of male rats / 中华劳动卫生职业病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effects of pyrethroids on nigrostriatal dopaminergic pathways in male rats and its mechanism.</p><p><b>METHODS</b>Different doses of permethrin (PM, 200, 400 mg/kg) and deltamethrin (DM, 6.25, 12.50 mg/kg) in corn oil were administered to rats by gavage once daily for ten days, then the contents of dopamine (DA) and its metabolites, 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the substantial nigra and striatum were analyzed by HPLC-fluorescence detection.</p><p><b>RESULTS</b>The contents of DA in striatum in four administered groups were decreased to a certain extent. DA in 6.25 mg/kg DM group [(6.14 +/- 0.57) microg/g wet weight] was lower than that in control group [(9.46 +/- 1.95) microg/g wet weight], P < 0.05. The turnover rate of DA in 200, 400 mg/kg PM and 6.25, 12.5 mg/kg DM groups increased by 133.33%, 166.67%, 166.67%, 266.67% respectively (P < 0.05 or P < 0.01), however there was no significant difference in DA and DOPAC in substantial nigra between control and administered groups.</p><p><b>CONCLUSION</b>DM may inhibit tyrosine hydroxylase and decrease the level of DA in striatum, and both pyrethroid pesticides may increase the metabolism of dopamine in striatum.</p>