The Analysis On Microcirculation Hemodynamic Changes Of Jejunal Mesentery With Acute Internal Capsule Hemorrhage In Rats

The Analysis on Microcirculation Hemodynamic Changes of Jejunal Mesentery with Acute Internal Capsule Hemorrhage in RatsObjective:1.To establish the model of intracerebral internal capsule hemorrhage of rats;2.To explore the changes of microcirculation hemodynarnic changes of jejunal mesentery before and after internal capsule hemorrhage,and make an important reference of microcirculation for stress ulcer after intemal capsule hemorrhage.Methods:1.Preparation of intracerebral internal capsule hemorrhagic animal model: Anesthetized rats,fix it on the rats stereotaxis instrument.According to the rats brain stereotaxic atlas,located the hind limb of internal capsule through stereotaxis instrument.An operation was made to open the skull by auger,100μl autologous venous blood from tail was injected into the hind limb of internal capsule through microinjector,and made the acute internal capsule hemorrhage animal model.2.Ethology evaluation before and after internal capsule hemorrhage:Using two ways to detect the rat's behavior 24 hours after the operation:2.1 Vibrissae-elicited forelimb placing test:Rats were held by their torsos,which allowed the forelimb to hang free.Independent testing of each forelimb was induced by brushing the respective vibrissae on the corner edge of a countertop. Intact animals place the forelimb ipsilateral to the stimulated vibrissae quickly onto the countertop.Depending on the extent of injury,placing of the forelimb contralateral to the injury in response to contralateral vibrissae contact with countertop may be impaired.In the experiments each rat was tested 10 times for each forelimb,and the percentage of trials in which the rat placed the appropriate forelimb on the edge of the countertop in response to the vibrissae stimulation was determined.2.2 Bederson's scoring criteria:Rats were held gently by the tail,suspended 10cm above the floor.Normal rats extend both forelimbs toward the floor.Rats that extended both forelimbs toward the floor and that had no other neurological deficit were assigned grade 0.Rats that with infarction consistently flexed the forelimb contralateral to the injured hemisphere and that had posture with extension to the earth were assigned grade 1;rats with 1 score sign had consistently reduced resistance to lateral push toward the paretic side,and were graded 2;Rats were then allowed to move about freely and were observed for circling behavior.Rats that circled toward the paretic side consistently were graded 3(pursuiting tail).3.Measurement of microcirculation hemodynamic changes of jejunal mesentery before and after internal capsule hemorrhage:Using the BI-2000 microcirculation surveying system,to observe the microvessel count,caliber,fluid state and flow rate of blood of mesentery microvessel before and after internal capsule hemorrhage.4.Preparation of pathological specimen of rat's brain tissue after internal capsule hemorrhage and pathomorphological observation of rat's brain tissue before and after internal capsule hemorrhage:After finishing the preparation of internal capsule hemorrhage animal model,took the brain tissue,fix them with 10% formaldehyde solution;paraffin embed,make coronal plane sections on internal capsule hemorrhage area.Through HE stain,observed their pathomorphological changes under the light microscope.5.Statistical analysis:Statistical software SPSS 15.0 was used.The differences of intestine mesentery microcirculation hemodynamic index in control group and brain hemorrhage groups were compared by analysis of variance(ANOVA),P=0.05.Results:1.The ethology test of the model of intracerebral internal capsule hemorrhage of rats through inject its autologous arterial blood:vibrissae-elicited forelimb placing test:In brain hemorrhage group,achievement ratio on hemorrhage side was 89%, achievement ratio on opposite side was 23%.It suggested that there were obvious allocinesia functional disturbance on rats after internal capsule hemorrhage; Bederson's scoring:All of the rats scored scored at 2.2.We confirmed that the hematoma were in the hind limb of internal capsule accurately through specimens and pathological section.We observed through light microscope after internal capsule hemorrhage that the position of hematorna was full of red blood cells and inflammatory cells infiltration around;and there were cell spaces distention and cellular swelling in the perienchyma of the hematoma, which suggested the happening of cerebral edema.3.Comparison of the changes of microvessel count before and after internal capsule hemorrhage.The result shows that the microvessel count decreased after the hemorrhage.4.Comparison of the changes of caliber of mesentery veinule before and after internal capsule hemorrhage.The result shows that the caliber turned to be more and more small,and vessel walls became more and more thicken and the color of vessel walls were getting more and more dark.In some groups the vessel walls of venule were broken,and the leucocyte rolled along the vessel wall and some of them even adhered to and leaked out of the wall.5.Comparison of the changes of fluid state and flow rate of mesentery veinule before and after internal capsule hemorrhage.The result shows that the flow rate of mesentery veinule decreased obviously.Conclusions:1.We can copy the accurate model of intracerebral internal capsule hemorrhage of rats by means of stereotactic method successfully.2.After internal capsule hemorrhage,the blood flow rate of mesentery veinule decreased obviously and the blood vessel contracted severely.The hemoperfusion and microvessel count decreased also.All these results indicate that there were microcirculation disturbance of mesentery microvessel after internal capsule hemorrhage,and mucosa of gastrointestinal tract were injured severely.It leaded to the stress ulcer ultimately.