Effects Of Exhausted Swimming Styles On The Expression Of NF-κB And INOS Gene In Rat PVN Of Hypothalamus

Objective To observe the differences and its regulation of the expression of NF-κB and iNOS after exhausted swimming exercise and investigate the regulation mechanism of hypothalamus on human maximal exercise.To direct movement training, increase movement result, resolve movement injury and to offer recovery theory .Methods Model rats were established by exhausted swimming exercise, seventy SD rats were randomly divided into control group(n=10) and exhausted swimming group(n=60). The brains of exhausted swimming group were removed at 0h,4h,8h,12h,16h,24h after seven-day exhausted exercise,to separate fresh brain tissue or to fix brain with paraform, the former to observe regulation of NF-κB in hypothalamus with western-bloting method ,the latter to observe the expression of NF-κB and iNOS by frozen section immunohistochemical SABC techniques.All dates were dealed with image analysis and SPSS13.0.Results Western-Bloting result suggest (1) the expression of NF-κB was extremely lower in control group and 0 hour group,the difference between these two groups was not statistically significant(P>0.05) .Compared with control group, the expression of NF-κB was higher in 4h,8h,12h and 16h groups, they have statistical significance (P<0.05).The expression of NF-κB in exhausted group peaked at 8h(p<0.05), decreased at 12-16h,and returned to normal levels at 24h(p>0.05).(2)The number of NF-κB stained immunoreactive neurons ( NF-κB + neurons) was extremely lower in hypothalamus in control group but incresed higher after exhausted swimming exercise and then descended in time course.(3)Compared with control group,the number of NF-κB+ neurons increased in pPVN in 0h group, but the both are not disparation (P>0.05), while increased at 4h(p<0.05),peaked at 8h(p<0.05), decreased at 12-16h,returned to normal levels at 24h (p>0.05).The number of NF-κB+ neurons in mPVN increased at 0-4h, peaked at 8h, returned to normal levels at 24h.(4)The number of iNOS+ neuron was low in control group, began to increse at 0-4h in pPVN and mPVN, peaked at 8h(p<0.05), then kept high level in other groups .Conclusion (1)The expression of NF-κB increased after exhausted swimming exercise in hypothalamus, which demonstrate that NF-κB participate the regulation of movement in CNS.(2)NF-κB can contribute to the expression of iNOS and cause neuron injury that due to brain tissue ischemia hypoxia and oxidative stress after exhausted exercise .