| Background:With the better thermal stability and uncertain toxic machanism,2,2’,3,3’,4,4’,5,5’-decabromodiphenyl ether(BDE209) is weidely applied in circuitboard, textiles, plastic products and building materials[1].The previous studiesshowed that it could pollute the environment via effusion or volatilization during themanufacture and accumulate inside the human body by food chains. China is thebiggest producers and consumers of BDE-209in the world. More and more evidencesindicate that it is the environmental pollution with the faster growing concentrationand longer durability. Its daily average absorbance by respiration is416ng[2] and theaverage concentration in the human plasma, breast milk and umbilical blood is9.472ng/g liquid weight，1.867ng/g liquid weight and78.103ng/g liquid weighrespectively[3]. The infants or the kids in growth period had been proved to be withthe higher DBE-209exposure levels than the adults [4], in view of their differences ofbody accumulation, developing abilities of detoxification and exclusion. Additionly,As the critical period of central system development, the brain of infant or child issensitive to any exogenuous toxicant, which arousing the public concerns of theinfluence to neural development by BDE-209. Prenatal asphyxia is the main cause of neuronal dysplasia, with restimated rate as70%~80%. The current morbidity of prenatal asphyxia is decresing apparently at theresult of improvement of medical services. However, the incidence of neuronaldysplasia remains to be1/1000around in view of its complicated reasons andmechanisms. The environmental chemicals attracted much attention for its leadingrole on neuronal development. Incidently, more and more evidences proved that theprenatal asphyxia could increase the risk of neuronal dysplasia influenced byenvironmental factors with combination insult of prenatal asphyxia. Moreover, less isknow for the environmental influence or risk factors to the pregnant outcomes inChina. With the little investments on environmental proteciton and heavy pollution tothe environment, so it is necessary to identify the combined inflences of prenatalasphyxia and exogenous factors on the neural development.Objective:To build the SD rat model of BDE-209prenatal exposure or combined with theasphyxia insult. The potential influence was preliminary studied for their combinedeffort to the neural reflexes and body development, the relevant gene ascapase-3.mTOR in the hippocampus, and the memory ability in morris water maze ofthe rat offspring, which could provide the theoretical evidences on the toxicology ofBDE-209and neural insult of asphyxia.Results:1. No difference was found on the general pain respone, auditory startleresponse and free fall acceleration between each group of the rat offsprings（P>0.05）.The significant difference was found on body righting, negative geotaxisand cliff avoidance of rat offsprings in asphyxia group(D,E,F) than the normoxicgroup.(A,B,C) But no dose-related toxicology was found with the exposure toBDE-209among the same group(A,B,C or D,E,F)（P>0.05）.2. Compared with group A, the significant difference was found on the timeduration in wire-suspension test in group E (0.6mgBDE-209+asphyxia)（P<0.05）.3. No differences were found between the rat offspring of each groups on thebody development as ear unfolding, development of fluff, lower incisor irruption, eyes opening, upper incisor irruption, development of fur,testes descendent.（P>0.05）4. No difference was found on the rat offspring between each group on timeconsuming or the percentage dwell time in the target quadrants of probe trial andacquisition task（P>0.05）.5. The caspase-3and mTOR gene expression by RT-PCR showed that, nodifference was found on the mTOR mRNA levels in the hippocampus of rat offspringbetween each group. Compare with groupA(control group), the significant differencewas found between each group in caspase-3mRNA levels (B,C,D,E,F)（P<0.05）.And result showed the dose-related effects of BDE-209.Conclusion:The results indicated the potential influence of BDE209prenatal exposurecombined with asphyxia to the rat offspring. |
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