电磁脉冲辐照对小鼠睾丸组织凋亡和转化生长因子β3表达的影响

Effects of electromagnetic pulses on apoptosis and TGF-β3 expression of mouse testis tissue

目的 观察电磁脉冲对小鼠睾丸组织凋亡和小鼠睾丸组织中转化生长因子（TGF）-β3表达的影响.方法 32只雄性BALB/c小鼠随机分为辐照组（接受场强200 kV/m,脉冲次数分别为100、200和400次的电磁脉冲全身辐照）和对照组（不做任何处理）,每组8只.用TUNEL法观察电磁脉冲对小鼠睾丸组织结构及凋亡的影响;RT-PCR、免疫荧光组织化学和Western blot测定电磁脉冲对小鼠睾丸组织中TGF-β3 mRNA和蛋白表达水平的影响.结果 100次和200次脉冲辐照后小鼠睾丸组织未见明显的病理变化,400次脉冲辐照后小鼠睾丸组织出现变性、脱落并引起小鼠睾丸组织凋亡率明显增加（P＜0.05）;Western blot结果显示,一定强度的电磁脉冲可引起小鼠睾丸组织TGF-β3表达增高,400次脉冲组表达明显增高（P＜0.05）;RT-PCR结果表明,400次脉冲辐照可引起小鼠睾丸组织TGF-β3 mRNA明显增加（P＜0.05）.结论 电磁脉冲辐照引起小鼠睾丸组织凋亡增加和TGF-β3表达增高,可能是电磁脉冲致小鼠血睾屏障通透性增加的机制之一.

Objective To investigate the effects of electromagnetic pulses （EMP） on the apoptosis and transforming growth factor beta 3 （TGF-β3） expression of mouse testis tissue.Methods Thirty-two male BALB/ c mice were randomly and equally divided into one control group and three EMP treated groups,which were whole-body exposed to EMP at 200 kV/m with 100,200,and 400 pulses,respectively.The control group received no treatment.The pathological changes and cell apoptosis in testis tissue were analyzed by TUNEL assay.The mRNA expression of TGF-β3 in testis tissue was determined by RT-PCR,and the protein expression of TGF-β3 was determined by immunohistochemistry and Western blot.Results No obvious pathological changes were found in testis tissue after EMP exposure at 200 kV/m with 100 and 200 pulses.However,after EMP exposure with 400 pulses,degeneration and shedding of testis tissue,accompanied by significant increase in apoptosis rate （P〈0.05）,was observed.The RT-PCR,immunohistochemistry,and Western blot showed that the expression of TGF-β3 mRNA and protein increased significantly after EMP exposure with 400 pulses as compared with that of the control group （P〈0.05）.Conclusion EMP exposure at 200 kV/m with 400 pulses increases the incidence of apoptosis and expression of TGF-β3 in mouse testis tissue,which is potentially one of the mechanisms by which EMP increases blood-testis barrier permeability in mice.