Study On The Correlation Between The Content Changes Of HYP In The Skeletal Muscle Of Rats' Postmortem Intervals

1.Study on the correlation between the content changes of HYP in the skeletal muscle of rats killed by different manners and these rats'postmortem intervalsObjective Through observing the model rats's dying process,which were killed by three different reasons(Electricity stroke, Suffocating, Bleeding),to study on the correlation between the content changes of Hydroxyproline in the skeletal muscle of these rats and their Postmortem intervals,making a statistical judgement.To provide a experimental basis for the estimation of postmortem interval.Methods 126 healthy SD rats were randomly and medially allocated into 3 groups.The 3 group rats ,which were killed by three different reasons (Electricity stroke, Suffocating, Bleeding), were put into the artificial climate box in which the rats were respectively conserved for 0h,24h,48h,72h,96h,120h and 168h,under the condition of constant 30℃and 50﹪humidity.Next,dissected the dead rats and got the adductors of their right legs,by using MRK-3 enzyme-labled instrument,at different death intervals,detected the contents of HYP in the skeletal muscle of the rats.Made a statistical analysis on the date and sougtht the correlation between the PMI and every variable ,worked out the coefficient about every parameter related with PMI and wrote out the regression equation.Finally,according to the analytic result,made comparisons among the content changes of HYP in the skeletal muscle of the rats killed by three different reasons.Results (1)In the course of making models,I observed that the Suffocating group rats'dying speed is the fastest of the three groups,the Electricity stroke group rats'is faster than the bleeding group rats',the bleeding group rats'dying speed is the slowest.(2)With the prolongation of PMI, the content of HYP in the skeletal muscle of the dead rats is gradually decreased and it has a linear correlation with the PMI.(3)The percentage ,which means the proportion that the content of HYP at death interval 168h occupies the content of HYP at death interval 0h,represents the HYP's decomposition speed.And according to the percentage,the Electricity stroke group rats'speed is the fastest(45.2%), the Suffocating group rats'is faster than the bleeding group rats'(49.7%),the bleeding group rats'speed is the slowest(54.9%).Conclusions The content of HYP in the skeletal muscle of the dead rats is gradually decreased,it suggests that the stability of HYP in dead organism is destroyed.The destruction maybe caused by the organism's enzymolysis and microbes'digestion,the destruction destroys the HYP's carboxy which determines the stability of the collagen protein.The conclusion mentioned above correlates the content of HYP with the PMI.HYP can hopefully be used in the medicolegal officer's practice to estimate the PMI. 2.A study on the correlation between injury interval and the content changes of HYP in rats'serum after whose femurs are fracturedObjective Set up the models ,whose femurs were fractured,to study on the correlation between the content changes of HYP in model rats'serum and the injury interval,making a statistical judgement. To provide a experimental basis for estimation of the injury interval.Methods 66 healthy SD rats were randomly and medially allocated into 11 groups.One control group,ten experimental group. The experimental group rats'right femurs were splinteredly fractured by a 250g weight dropper dropping from 200cm height. By using MRK3 enzyme-labled instrument,at different injury intervals(0d,1d,3d,5d,7d,11d,14d,17d,21d,24d,28d),detected the content of HYP in rats'serum, Made a statistical analysis on the date and sougtht the correlation between the injury interval and every variable ,worked out the coefficient about every parameter related with injury interval and wrote out the regression equation. Finally,according to the analytic result, made comparisons among the content changes of HYP in rats'serum, after whose femurs were fractured,in different groups.Results (1)The concentration of HYP in rats'serum was gradually increasing within the 14 days since the rats'femurs were fractured.(2)At the 14th day,the concentration of HYP got to the peak.Then,from the 13th day to the 28th day,the concentration of HYP in rats'serum was gradually decreasing.(3)At the 28th day,the concentration of HYP in the experimental group rats'serum was still thicker than the control group rats'.Conclusion Compared with the concentration of HYP in the control group rats'serum,during a certain period of time,the concentration of HYP in the experimental group rats'serum has a tendency to increase,suggests that the HYP participates in the restoration of the fractured bone.There is a correlation between the concentration change and the injury interval after fracture. The conclusion mentioned above can hopefully be used in the medicolegal officer's practice to estimate the injury interval of fracture's intermediate and advanced stages.