Aprotinin In The Rat Brain Around The Hematoma With Secondary Injury Intervention Experiments

Objective: To study mechanisms of aprotinin protecting brain and the effect of the mechanisms on inflammation and apoptosis after intracerebral hemorrhage, we investigated the changes of interleukin-1β and caspase-3 in brain regions around the hematoma by the intervension of aprotinin.Methods: Intracerebral hemorrhagic model was induced utilizing the local injection of collagenase Ⅶ into the basal ganglia with sterile technique. Aprotinin was used as the intervension drug. In different times, the changes of interleukin-1βand caspase-3 were detected by immunohistochemistry, IL-1 protein level by ELISA, apoptosis levels by TUNEL and HE techniques, Brain Water Content (BWC) by dying-weighing method, the level of inflammation in PHT by HE, neurological severity scores by Berderson's method.Results: 1. In model group(MG), the IL-1β positive cells in PHT began to increase slightly at 6 hours compared with sham group(SG), increased significantly at 12 hours, reached the peak at 48～72 hours, still remained some at 7 days. In aprotinin-treated group(ATG), aprotinin reduced the positive cells, especially at 48 hours, 72 hours, 7 days(compared with MG, P<0.01).2. In SG, the content of IL-1βin PHT began to increase at 6 hours after ICH, reached the peak at 24～48 hours, was higher than SM at 168 hours(P<0.05); In ATG the content of all times dicreased significantly compared with MG (P<0.01), amounted to the level of SM at 168 hours(P>0.05).3. In MG, the caspase-3 positive cells in PHT began to increase at 6 hours after hemorrhage(compared with SG, P<0.01), the amount of positive cells reached the peak at 48 hours, decreased slightly at 3 days and significantly at 7 days. In ATG, aprotinin reduced the protein expression of caspase-3 at most times exclude 6 hours, especially at 24 hours,48 hours, 3 days(compared with MG, P<0.01).4. In MG, TUNEL positive cell in PHTappeared at 6 hours after ICH, increased markedly at 24 hours, reached the peak at 3 days, still remained some at 7 days, there was a remarkable difference compared with all times of the SG(exclude 6h, P <0.01). In ATG, aprotinin reduced the amount of TUNEL positve cell, especially at 24 hours,48 hours ,72 hours, 7 days(compared with MG, P<0.01).5. In MG BWC increased at 6 hours, increased markedly at 12 hours, the peak at 48 hours, decreased markedly at 7 days (compared with SG, P<0.05). In ATG, aprotinin reduced BWC especially at 48 hours, 3 days(P<0.01).6. By HE staining,very few neutrophil infiltration was observed in SG; In MG, neutrophil infiltration increased slightly at 6 hours, markedly at 24 hours, reached the maximum at 48 hours and 72 hours, then decreased . In ATG ,there was a significant decrease at 24,48,72,168 hours(compare with MG,P<0.01).7. It showed no significant difference between MG and ATG. however, there was greatly difference at 24 ,48,72,168 hours between these two groups.Conclusion: Aprotinin could reduce the IL-1βprotein level in PHT, alleviate greatly the inflammation following ICH; Aprotinin could reduce the apoptosis after ICH, which probably related with inhibiting Caspase-3 expression or inflammation response.