Expression Of TM After Cerebral Contusion Of Rat

Objective:To examine the expression trend of TM in the brain after cerebralcontusion of rat by ELISA,immunohistochemical SABC,in order to explore theapplication for estimating the early time of brain contusion in forensic medicineaspect.Methods:The 64 SD rats were divided into control group (contain 8 rats) andexperimental group (contain 56 rats) randomly. Experimental group were divided into7 subgroup by dating of wound. After enforced intraperitoneal anesthesia, the ratmodel of cerebral contusion was founded by Feeney,s method. The cerebral contusionwas performed on the side of 3mm from the middle of skull of experimental animalby using a gravitational force of a free falling weight. Tissue samples were fixed;paraffin embedded, sectioned and then stained by H.E performed to identify the injurysite and injury time, the pathologic changes of brain injury, expression of TM atdifferent internals within 7 days after brain injury by the light microscope. Take 5mlof blood from the heart of rat respectively at 1h,4h,8h,12h,24h,3d,7d (8 ratsin each subgroup). After low temperature centrifugalization , placed in -70℃storedfor detection. The 100mg of brain tissue were cut at above time mentioned and thenthe samples were made into paraffin. Rats in control group were dealt as same as ratsin experimental group except for gravitational force. To examine the expression trendof TM in the brain after cerebral contusion of rat by ELISA,immunohistochemicalSABC, analyzed by use of the computer image analysis technology, contrast withuninjured group .The results were assessed by statistic analysis.Results: (1) The expression of TM could be detected increased at 4h afterinjury, peaked at 24h. Positive cells decreased with the prolongation of injury time.Little expression was found at 3d but still higher than the control. Return to the levelof control at 7d. (2) The expression of TM in cerebral intravascular endothelialexpression pattern showed the same variation with the TM level in plasma.Conclusion:The time-dependent expression of TM in the plasma and braintissue after cerebral contusion of rat could be applied in dating of wound for braincontusion. ELISA and Immunochemical is simple and convenient and refer to forensicstudy.