Correlation Analysis On HPA Axis Change And Glucolipid Metabolism Of Rats With Type Ⅱ Diabetes Under Stimulation Of Swimming

Objective：Discuss rat diabetic model induced by STZ and high fat diets， anddiscover impacts from swimming and HPA axis center regulation; Provide theoreticsupport for developing exercise prescription against type2diabetes.Methods： Put50SD male rats（SPF class）with8weeks old into groups including： normal controls（group C）， model group after8weeks（M8group）， model group after16weeks（M16group）， model group with exercises after8weeks（ME8group） and modelgroup with exercises after16weeks（ME16group）. The experiment will last for16weeks during which rats in all groups will swim everyday without burden. Duration is15min/day in the first week and will increase by15min every week until60min/day.Swim training will last for16weeks with5days a week. After8weeks and16weeks，use enzyme immunoassay method to determine plasma insulin level， serumcorticosterone level and BDNF level; use automatic biochemical analyzer to determineblood glucose and lipids level. Results：（1）5weeks high fat diet with injecting smalldose STZ （35mg/kgbw） into abdominal cavity can successfully duplicate rat modelwith type II diabetes；（2）Compared with normal control C， the serum corticosteronelevel in M8and M16has increased. And it is on a rise trend along with the time. Theformer one has significant difference （P<0.05）. And the latter one has extremedifference （P<0.01）；（3） Group M16and group ME16have significant difference（P<0.05）. No significant difference can be found in serum corticosterone levelbetween group M8and group ME8（P＞0.05）；（4）Compared with normal control，Serum BDNF level in M8and M16has decreased. And the former one has significantdifference （P<0.05）. And the latter one has extreme difference （P<0.01）. SerumBDNF level in ME8has increased more than that of M8， but no significant difference can be found （P>0.05）. In contrary with M16， Serum BDNF level in ME16hasincreased significantly with extreme difference（P＜0.01）；（5）Compared with normalcontrol， blood glucose and lipids level in M8and M16has increased significantly withextreme difference（P＜0.01）；（6）Blood glucose level between group M8and groupME8has extreme difference （P＜0.01）. Meanwhile， significant difference in bloodglucose level can be found between group M16and ME16（P＜0.05）. Blood lipids levelbetween exercise group and model group has significant difference （P<0.05）. Nosignificant difference can be identified in blood lipids level between group M8andM16， ME8and ME16respectively；（7）Correlation analysis of all kinds of index.Serum corticosterone level has high degree of correlation with plasma insulin level，blood sugar level and blood serum BDNF. The r value is0.84，0.96and0.84respectively. However， it has a negative correlation with blood lipids with an r value of-0.45. Blood serum BDNF has a high degree of positive correlation （r=0.86） withblood sugar level but a middle positive correlation（r=0.55） with plasma insulin level.It has a negative correlation with blood lipids level with a r value of-0.32.Conclusions：（1）5weeks high fat diet with injecting small dose STZ（35mg/kgbw） into abdominal cavity can successfully duplicate rat model with type IIdiabetes;（2） Compared with normal controls， rats in model groups have reflectedglycolipid metabolic disorder featured by soaring blood glucose and lipids level.Consequently，peripheral sustained high corticosterone level cause HPA axis functionaldisorder. And expression of serum BDNF is inhibited.（3）8weeks swim and16weeks swim can effectively decrease the blood glucose and lipids level， and ease themetabolic disorder.（4） Improvements in ME16group are more substancial whichmay contributed by central control mechanisms featured by low corticosterone level andhigh BDNF level after long term swim exercises.