Effect Of Stereotaxis Hematoma Aspiration On Aquaporin-4 Expression After Intracerebral Hemorrhage In Rat

Objective:Intracerebral hemorrhage ( ICH ) is a common disease in nervous system.it is characteristic of high morbidity,mortality,disability rate.Its main death reason is the cerebral hernia which is induced by intracal occupation of acute intracerebral hematoma and encephaledema that is resulted by hematoma damages brain tissue. Thus,removing intracerebral hematoma in time, which can make the secondary brain edema relieve, there is a important significance to reduce mortality of intracerebral hemorrhage. Aquaporin-4 is a cell membrane transport protein ,which is concerned with permeation of water and is discovered in recent years. Our experiment study is using directional hematoma aspiration on the basis of the model of intracerebral hemorrhage(ICH) was induced in rats by local injection of type IV bacterial collagenase into the caudate nucleus, to dynamically observe aquaporin-4(AQP-4)expressinon and changes of brain edema in perihematoma after intracerebral hemorrhage (ICH) and the hematoma was aspirated , discussion on the effect of stereotaxis hematoma aspiration on changes of brain edema and aquaporin-4 expressinon, as well as its mechanisms, and discussion on the correlation of aquaporin-4 and brain edema.Methods:one hunderd thirty SD rats were randomly divided into three groups: slam-operation group(n=10),intracerebral hemorrhage(ICH) group (n=60),the group in which hematoma was aspirated after intracerebral hemorrhage(n=60). The last two groups was further divided into groups of 6 hours,12 hours,24 hours,3 days,5days,7 days(n=10 in each group). The model of intracerebral hemorrhage(ICH) was induced in rats by local injection of type IV bacterial collagenase into the caudate nucleus, the group of hematoma aspirating in which hematoma was aspirated after intracerebral hemorrhage.The immunohistochemical(IHC) expression of AQP-4 after intracerebral hemorrhage were determined using immuno- histochemistry and brain water content measure by using the dry-wet weight assay. The level of brain edema was assayed by measuring brain water content.Results: The brain water content increased gradually from12hours after ICH(P<0.05)and peaked at day 3(P<0.05), afterwards ,it began to reduce, it was slightly higher than slam-operation group at day 7(P<0.05).In the group of hematoma aspirating, the brain water content increased gradually from 6 hours after hematoma was aspirated(P<0.05)and peaked at 24h(P<0.05), afterwards ,it began to reduce, it was obviously reduced at day 7. To control with intracerebral hemorrhage group, the brain water content increased obviously at 6hours in the the group of hematoma aspirating(P<0.05)and there is no difference at 24h between them, it was obviously reduced at day 3 and 5(P<0.05).The AQP-4 expression around hematoma increased at 12h(P<0.05) after ICH that was induced in rats by local injection of type IV bacterial collage-nase into the caudate nucleus and reached a peak at day 3(P<0.05), whose A of the AQP-4 expression around hematoma is (0.54±0.05), afterwards, the AQP-4 expression around hematoma reduced gradually , It remainded higher than normal level at 7d. In the group of hematoma aspirating, The AQP-4 expression around hematoma increased at 12h(P<0.05)and reached a peak at day 24h(P<0.05), whose A of the AQP-4 expression around hematoma is (0.44±0.05 ) , afterwards, the AQP-4 expression around hematoma reduced gradually, the A of the AQP-4 expression around hematoma is (0.35±0.05) at day 5, which is still higher than the slam-operation,s, it is normal at day 7. To control with intracerebral hemorrhage group, the A of the AQP-4 expression around hematoma at 24h is(0.44±0.05),which is higher than which is at 24h after ICH(P<0.05), the A of the AQP-4 expression around hematoma at day3 and 5 is (0.54±0.05),(0.41±0.06),which is lower obviously than which after ICH, there is no difference at 7d.Conclusion: 1.The aquaporin-4 expression which is in the brain tissue can be weaken obviously after 24 hours and encephaledema can be reduced after intracerebral hemorrhage in rats after 3 days after the hematoma was aspirated. 2.According to the change of the encephaledema after hematoma was aspirated , prompt necessary dehydration drugs will be used in the clinical. 3.The expression level of AQP-4 around hematoma after intracerebral hemorrhage and hematoma was aspirated was positively correlated with the brain water content.