A Study Of The Toxic Effects Of Cigarette Smoking On Learning And Memory In Male Rats And Offspring

Objective: Simulate the crowd in exposure in a smoking environment condition,to build different doses and different time the passive smoking in the male rat model of smoking,to evaluation of passive smoking on male offspring rats learning and memory.Method: 150 SD rats(100malerats and 50 female rats)were randomly divided into exposure group and blank control group.Male rats were copulated with female rats as the ratio of 1:1 for one week before execution,newborn rats were observed for 21 days after birth.After exposure measured the protein content,SOD activity,MDA content and NO content in brain tissues.The morphological changes of brain tissue and hippocampus were observed by HE staining.The expression of c-Fos and the expression of BDNF in hippocampus were detected by immunohistochemistry.NR2 B mRNA and protein in brain tissue Tau and hippocampus were detected by RT-PCR and Western Blot.Results: 1.The body weight of male and female rats exposed to 4-week exposure decreased with the increase of exposure dose(P<0.05).2.The brain tissue coefficient of male rats in each exposure time group was lower than that in the control group,the difference was statistically significant(P<0.05).The brain tissue index of offspring rats in each exposure time group was lower than that in the control group except 4 weeks group,the difference was statistically significant(P<0.05).3.The activity of SOD in the brain of male rats was lower than that of the control group,The difference was statistically significant(P<0.05).The activity of SOD in the brain of the offspring was lower than that in the control group.4.The content of MDA in the brain of male rats was lower than that of the control group,the difference was statistically significant(P<0.05).The content of MDA in the brain of the offspring was lower than that of the control group,the difference was statistically significant(P<0.05).5.The content of NO in the brain of male rats exposed to different exposure time was lower than that of the control group.The content of NO in 6-week group was lower than that in control group,the difference was statistically significant(P<0.05).6.Compared with the control group,the latency of the male rats was significantly higher than that of the control group,the difference was statistically significant(P<0.05),swimming distance results compared with the control group,the difference was statistically significant(P<0.05).Results of latent period compared with the control group,the difference was statistically significant(P<0.05).Swimming distance results compared with the control group,the difference was statistically significant(P<0.05).7.In the space exploratory experiment,the male rats in the low,middle and high dose groups,the different exposure time group,the difference was statistically significant(P<0.05).Compared with the control group,the offspring exposure of 4-week-old rats was lower,the difference was statistically significant(P<0.05).8.Brain tissue and hippocampus HE staining was found,in the exposed group,the brain tissue and the hippocampus of male rats and their offspring were damaged to different degrees,and the damage was more obvious with the exposure time prolonged.9.The content of fos protein in the brain tissue of male rats exposed to various exposure time groups increased compared with the control group,the difference was statistically significant(P<0.05).The content of fos protein in the brain tissue of the offspring rats increased with the exposure time,the difference was statistically significant(P<0.05).The expression of BDNF protein in the hippocampus of male rats exposed to different exposure time groups was higher than that of the control group,the difference was statistically significant(P<0.05).The expression of BDNF protein in the hippocampus of the offspring rats was increased compared with the control group,the difference was statistically significant(P<0.05).10.Compared with control group,the expression of taumRNA and protein in the high dose group increased significantly(P<0.05),the expression of taumRNA and protein in the high dose group was significantly higher than that in the control group at 8 weeks(P<0.05).Compared with control group,the expression of NR2 BmRNA and protein in the high dose group decreased significantly(P<0.05),the expression of NR2 BmRNA and protein in the high dose group was significantly lower than that in the control group at 8 weeks(P<0.05).Conclusion: Smoking can cause damage to the behavior of male rats and offspring;cigarette exposure can also damage the brain and hippocampus of male rats and offspring;made brain and hippocampus tissue protein and mRNA expression abnormalities,suggest that smoking can lead to male rats and offspring learning and memory damage.