Effect of nonylphenol exposure during pregnancy on the growth, development and neurobehavior of rat offspring

Objective:To investigate the effect of nonylphenol (NP) exposure during pregnancy on the growth, development and neurobehavior of rat offspring.Methods:Pregnant SD rats were infected with NP during the whole pregnancy.Negative control group(corn oil), low-dose NP group(50 mg/kg), medium-dose NP group(100 mg/kg), high-dose NP group (200 mg/kg) and positive control group (diethylstilbestrol, Des, 30 μg/kg) were set.The growth and development of the rat offspring were observed.The open field experiment was used to test the autonomic activity and anxious behavior of the rat offspring, the forced swimming experiment was used to test their depression, and the Morris water maze experiment was used to test their learning and memory abilities.Results:Compared with the negative control group, the body weight of rat offspring in the medium-dose NP group and the positive control group was lower on day 0 after birth(PND 0), the body weight and thyroid weight of rat offspring in the high-dose NP group and the positive control group were lower on day 23 after birth (PND 23), and the liver coefficient of rat offspring in the medium-dose NP group was lower.Testis weight decreased in the medium and high-dose NP groups and positive control group (all P< 0.05).In the open field experiment, compared with the negative control group, the total movement distance in all dose NP groups and the positive control group was significantly reduced, the residence time in the central area in the high-dose NP group and positive control group was significantly shortened, the proportion of distance in the low-dose NP group and positive control group was significantly reduced, and the total number of mobile cells in the medium-dose NP group, high-dose NP group and positive control group was reduced (P< 0.05).The results of depression-like behavior test showed that compared with the negative control group, the escape latency was significantly prolonged and the average swimming distance was shortened in the low-dose NP group on day 4; the escape latency was prolonged and the average swimming distance was shortened in the medium-dose NP group on day 5(all P< 0.05).Morris water maze results showed that the percentage of time in the third quadrant in the low-dose NP group and positive control group was lower than that in the negative control group, and the average speed in the medium-dose NP group was lower than that in the negative control group(all P< 0.05).Conclusion:Exposure to NP during pregnancy can result in impaired growth and development of offspring, as well as neurobehavioral damage such as depression, anxiety and reduced learning and memory abilities, which will lead to adverse effect on both short-term and long-term growth and neural development.