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The purpose is more and more evidence that air pollution a serious threat to human health, but also have a negative impact on pregnant women and fetal development, resulting in an increase in birth defects in children born population quality. Fetal growth process by PM (Airborne Particulate Matter, PM) pollutants, has begun to be taken seriously. In this experiment, the ICR mice as experimental subjects, PM intervention in pregnant rats and pregnant rats PM contact model. Gestational age given phosphate buffer (Phosphate Buffered Saline, PBS) blank control and different concentrations of PM suspension compare embryo development groups, to explore the the PM mouse embryo development of acute toxic effects, dose - response relationship possible mechanisms, to lay the foundation for further in-depth study of atmospheric PM on human fetal development. Method adult healthy and clean female and male ICR mice 40, conventional methods after mating, pregnant rats were randomly divided into five groups according to the weight close to 8 in each group. Dams pregnancy the day until the termination of pregnancy, maternal completely by ether anesthesia, according to the GVS Rao's improved the PM suspension airway planting method, the experimental group was given every three days time PM the suspension, concentration: ultra-high dose, 69.2 μg / μl, high doses of 1.85μg / μl in dose 0.52μg / μl, a low dose of 0.09μg / μl; blank control group given once every three days PBS. Detection indicators: 1) the dams 1,7,14,18 days of pregnancy weight; 2) maternal pregnancy days, the deformities number of pups, stillbirths number, the number of live births to absorb the number of births; 3) was born offspring weight body length and tail length; 4) intrauterine growth retardation (IUGR: Intrauterine Growth Retardation) rate; 5) liver system, pulmonary system number; 6) histological changes of the liver, lung; 7) pulmonary CYP1A1 gene mRNA, liver CYP1A2 mRNA expression; 8) lung CYP1A1 gene, hepatic CYP1A2 gene protein. 1, pregnant mice weight growth: pregnant the first 14 days and 18 days of ultra-high-dose group compared with the blank control group and three experimental groups, the weight gain slowed down, the difference was significant significance (P lt; 0.05) . 2 days of pregnancy in pregnant rats: ultra-high-dose group compared with the blank control group and three experimental groups, reducing the number of days of pregnancy, the difference was statistically significant (P lt; 0.05). 3, birth weight of offspring: the ultra-high-dose group compared with the control group, the body weight of pups decreased significantly, the difference was statistically significant (P lt; 0.05); low, medium and high dose groups compared with the blank control group the pups weight downward trend, but the difference was not statistically significant (P gt; 0.05). IUGR rate: ultra-high-dose group compared with the control group, IUGR rate has significantly increased, the difference was statistically significant (P lt; 0.05); low, medium and high dose groups compared with the control group, IUGR rate upward trend, but the difference was not significant significance (P gt; 0.05); compared to the ultra-high-dose group and the control group and the other concentration groups, IUGR rate increased significantly, and the difference was statistically significant (P lt; 0.05). 4, the pups body length and tail length: the ultra-high-dose group and the control group and the other three experimental groups (compared to body length and tail length are shorter, the difference was statistically significant (P lt; 0.05). embryonic death: the ultra-high-dose group compared with the blank control group and three experimental groups, mortality was increased, and the difference was statistically significant (P lt; 0.05) 6 groups to compare the number of pups dirty system : ultra-high-dose group compared with the PBS control group and three experimental groups were significantly higher than the number of pulmonary system, the number of liver system, the difference was significant (P lt; 0.05). 7, pulmonary CYP1A1 gene mRNA, hepatic CYP1A2 mRNA expression:, high and ultra-high-dose group expression were significantly increased, and the difference was statistically significant (P lt; 0.05); pups lung CYP1A1 gene mRNA expression was increased gradually with exposure concentration increased. lung CYP1A1 gene, the liver CYP1A2 gene protein expression: expression of ultra-high-dose group were significantly increased, the difference was statistically significant (P lt; 0.05); groups pups expression was increased gradually with exposure concentration increased. conclusions of the animal experiments Preliminary confirmed: 1. making mode success: exposure to PM in pregnant mice especially the ultra-high-dose group, reduced weight gain, reduced pregnancy day number, for embryonic developmental toxic effects significantly, resulting in adverse pregnancy outcomes, such as premature birth, low birth weight, IUGR, stillbirth, absorbed fetus. 2, ultra-high doses of 20,000 μg/m3 g PM have an adverse effect on the embryo, resulting in adverse pregnancy outcomes. 3, higher concentrations of PM and its adsorption of certain substances, possibly through the placenta pups, liver, lung damage. 4 PM role, CYP1A1 mRNA and of CYP1A2 mRNA of CYP1A1 protein and CYP1A2 protein expression showed a upward trend, the United States Environmental Protection Agency (The US Environmental Protection Agency, EPA) for atmospheric particulate matter ambient air quality standard formulation is safe on maternal and embryonic, the largest city in PM10 concentration range should be between 26 to 534μg/m3, within 24 hours of standard 150μg / m ~~.
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