| Recently research on the non-skeletal tissue by fluorine especially on the reproduction system is caused men's attention,we found that the rate of infertility in fluorine poisoning resident is higher than the non-fluorine poisoning resident,and the sperm quantity and quality is low.Research have indicated that the fluorine can induce rats sperm reduce,activity ratio decline,deformity ratio ascensus,it alse induce testis changes and hormone changes in blood serum.Plenty of research have explained that appropriate dose of zinc can antagonize the lipid peroxidation and DNA damage induced by fluorine,it also antagonize cell apoptosis.Bcl-2 protein,Bax protein is the most important protein during the cell apoptosis. Bcl-2 gene belongs to apoptosis depression gene,Bax gene belongs to apoptosis promote gene.Bcl-2 protein and Bax protein existence as homodimer or heterodimer in the cell.When the bax gene express increasing,the ratio of Bax/Bax homodimer increase,it can promote the cell apoptosis,and then,when the bcl-2 gene express increasing,the ratio of Bcl-2/Bax heterodimer increasing,it can inhibition cell apoptosis.So the ratio of Bcl-2/Bax protein is considered as determine the cell fate.As it report,appropriate dose of zinc can inhibition cell apoptosis,and there is little reporter concerned with zinc repress the male reproduction system damage.This experiment detect the express of Bcl-2 protein,Bax protein in the germ cell to invest the mechanism of zinc repress the male reproduction system damage. Materials and Methods1 Fifty healthy male rats weighted 68.5 to 92.5 gram were allocated into five group randomly.There were ten rats in every group.The five experimental group were control group,fluorine treatment group,fluorine and low-dose zinc treatment,fluorine and middle-dose zinc treatment,fluorine and high-dose zinc treatment group.The NaF and ZnSO4 dosage for every group were 0,25mg/kgBw·d(NaF),25mg/kgBw·d(NaF) and 4mg/kgBw·d(ZnSO4),25mg/kgBw·d(NaF) and 20mg/kgBw·d(ZnSO4), 25mg/kgBw·d(NaF) and 50mg/kgBw·d(ZnSO4) respectively.2 Detect index:In the way ofintragastric administration for six weeks.At the end of the experimental,after putting the rat to death,both testis and epididymide were dissected out and weighted for calculating their organic coefficient,and analyzed for the counts of sperm,the rates of sperm mobility and sperm aberration.The levels of serum testosterone(T) were radio immunochemically examined.The levels of LDH in the testis was examined.The content of NaF in testis was measured by using fluorine selective electrode.Bcl-2,Bax expression in germ cells was measured by immunohistochemical study.3 In this study,all the data was analyzed with the statistical software of SPSS12.0 package,One-way analysis of variance(ANOVA) and non-parametric tests were used to in the statistic.There was significant difference whenαwas 0.05.Results1 There is no differences in body weight,right testis weight,fight epididymis weight,the radio of right testis and fight epididymis during the five groups(P＞0.05).2 The sperm count of three zinc add groups is higher than that from the fluorine group(P＜0.05),the sperm count of high dose zinc add group and control group is no significantly(P＞0.05),the sperm count of fluoridne group,low zinc dose add group and high zinc dose add group is lower than that from control group(P＜0.05).3 The ratio of sperm activity of middle zinc dose add group and high zinc dose add group is high than that from fluorine group(P＜0.005),there have no difference between low zinc dose add group and fluorine group(P＞0.005),fluorine group,low zinc dose add group,high zinc dose group is lower than that from control group(P＜0.005),and there have no difference between middle zinc dose add group and control group(P＞0.005).4 The ratio of sperm deformity of low zinc and middle zinc dose add groups is lower than that from the fluorine group(P＜0.005),there have on difference between high zinc dose add group and fluorine group(P＞0.005),fluorine group,low and middle zinc dose add group is higher than that from control group(P＜0.005),and there have no difference between middle zinc dose add group and control group(P＞0.005).5 The level of fluorine of testis in every experimental group was significantly higher than that of control group(P＜0.05).And it was significantly higher in fluorine treatment group,fluorine and low-dose zinc treatment,fluorine and high-dose zinc treatment group than that in fluorine and mid-dose zinc treatment group(P＜0.05). comparing to fluorine treatment group,fluorine and low-dose zinc treatment group, testis fluoride in fluorine and high-dose zinc treatment group significantly increased(P＜0.05).6 The T levels in serum from the three dose add zinc group is higher than that from fluorine group and control group(P＜0.05),and there is no difference between the fluorine group and control group(P＞0.05).7 The levels of LDH were significantly reduced(P＜0.005) in fluorine group, group of fluorine plus low-dose zinc and fluorine plus high-dose zinc compared to control group.There were significant differences(P＜0.005) between group of fluorine plus mid-dose zinc and fluorine plus high-dose zinc in the levels of LDH.8 Compared to control rat,the microstructure of testis were normal relatively,but it disappeared and were loosened,the number of mature sperm was reduced in the other three groups.9 Bcl-2 expression in germ cells of every zinc treatment groups were significantly higher than that of fluorine treatment group(P＜0.005),mid-dose zinc treatment group and high-dose treatment group was significantly higher than that of control group(P＜0.005).There had no significantly between low-dose zinc treatment group and control group.Bax expression in germ cells of mid-dose treatment group was significantly lower than that of fluorine treatment group(P＜0.005),high-dose zinc treatment group was significantly higher than that of fluorine treatment group(P＜0.005),fluorine treatment,low-dose zinc and high-dose treatment groups were significantly higher than that of control group(P＜0.005).Conclusions1 Zinc can antagonize the reproductive toxicity of fluoride in male rats on molecular level by increase Bcl-2 protein expression and decrease Bax protein expression in germ cells.2 The effect of zinc antagonize the reproductive toxicity of fluoride in male rats rely on the dose.Middle dose of zinc(2Omg/kgBw·d) have the best effect,low dose of zinc(4mg/kgBw·d) and high dose of zinc(50mg/kgBw·d) have no effect,and high dose of zinc may have synergism with sodium fluoride. |
