Metabolism and distribution of arsenic in offspring rats after exposure to arsenic via drinking water / 中国地方病学杂志

ABSTRACT

Objective To observe the metabolism and distribution of arsenic in liver and brain of offspring rata by exposure to arsenic of pregnant rats or lactation dams and weaned pups,and explore if arsenic could penetrate the placental barrier,lactation barrier and blood brain barrier. Methods The Wistar female rots were randomly divided into four groups according to body weights,12 in each group,and were fed with drinking water that contained arsenic(NaAsO_2) 0,10,50,100 mg/L beginning from the gestafional day 6 until pups 42 days old. Pups were separately sacrificed on postnatal day(PND) 0,15,28,42. Arsenic in liver and brain of offspring rots and in breast milk was examined by atomic absorption speetrophotometer with an arsenic speeiation pretreatment system. Results Concentration of iAs,MMA,DMA of brain in 50,100 mg/L groups were higher than that of 0 mg/L group[0,0,0,(7.3±6.6),0,(44.2±27.4)ng/g]on PND 0,42[iAs (120.0±46.0),(195.5±125.3),(216.5±278.4),(176.6±151.8) ng/g; M MA (47.2±18.1),(199.6±389.1),(47.4±55.2),(82.7±79.2) ng/g; DMA (984.3±377.4),(2222.1±1433.2),(998.1±368.3),(1781.3±715.7)ng/g,all P < 0.05]. Concentration of DMA of brain in 50,100 mg/L groups were higher than that of 0 mg/L group[(13.9±18.1),(50.6±98.3)ng/g]on PND 15,28 [(270.3±73.1),(323.9±72.7),(758.7±245.9),(1020.6±383.6) ng/g,all P < 0.05]. Concentration of iAs,DMA of liver in 10,50,100 mg/L groups were higher than that of 0 mg/L group [(1.4±3.5),(49.7± 47.1),0,(100.4±30.2)ng/g]on PND 28,42 [iAs (37.5±28.1),(268.8±246.4),(307.2±339.9),(15.4±9.4),(479.1±161.1),(408.4±51.9)ng/g;DMA (594.5±148.8),(3181.9±519.0),(4834.2±2568.4),(1061.8± 85.2),(3697.1±553.7),(4120.0±732.8) ng/g,all P < 0.05]. Concentration of DMA of liver in 10,50,100 mg/L groups were higher than that of 0 mg/L group[(13.2±20.5)ng/g]on PND 15[(182.0±60,2),(637.6±90.0),(1458.7±196.3)ng/g,all P < 0.05]. Concentration of arsenicals of liver and brain showed a dose-dependent increase. The concentrations of DMA of breast milk in 50,100 mg/L groups were also higher than that of 0 mg/L group[(9.8±13.4),0 ng/g]on PND 0,15 [(182.3±85.9),(372.2±203.9),(124.2±33.1),(244.4±196.5)ng/g,all P < 0.05]. In the analysis of the change of arsenic on different postnatal day,we found the concentration of iAs,MMA,DMA,TMA in liver and brain of pups all decreased on postnatal day 15,and was lower than that on PND 0,28 and 42. Conclusions The distribution of arsenic and methyl-metabolism in liver and brain of pups is related with arsenic exposure dose. Arsenic can penetrate the placenta and blood brain barrier easily and lactation can hinder arsenic intake in some extent.