Research In Dynamic Expression Of AQP4 Gene During The Stage Of Traumatic Brain Injury In Rats

Objective:To observe the expression of aquaporin-4(AQP4) and its correlation with traumatic brain injury during the stage of traumatic brain injury , and to reveal the role of aquaporin-4(AQP4) in the development of traumatic brain injuries (TBI) in rats .Methods:We choosed inbred , clean and ripe male wistar rats . Their age was 8 weeks , and their weight was controlled between 250 and 300g . 168 Wistar rats were divided randomly into control groupa(D) and experimental group . The experimental group was divided into light(A) , midrange(B) , and ponderosus(C) group during the stage of traumatic brain injury . The each group was divided into 0.5h , 2h , 6h , 12h , 24h , 48h and 72h group . The rats were made into sap pressure assault and traumatic brain injuries (TBI) model . The rats were decapitated , and the brain was taken out of 0.5h , 2h , 6h , 12h , 24h , 48h and 72h after traumatic brain injuries (TBI) in each group . The brain tissue was take out of from the center of injured region .We adopted RT-PCR technology , and detected expression of AQP4mRNA in the brain tissue of rats .Results: The expression of AQP4mRNA in the brain tissue of experimental group was compared with that in the control group . The expression of AQP4mRNA began to increase 6h after ponderosus traumatic brain injuries (TBI) , and the expression was higher 0.5h after ponderosus traumatic brain injuries (TBI) , and the expression was even higher 12h after ponderosus traumatic brain injuries (TBI) , and the expression reached the peak 24h after ponderosus traumatic brain injuries (TBI) . And the expression of AQP4mRNA still kept high level 3d after ponderosus traumatic brain injuries (TBI) . There were significant difference . The change tendency of expression after light and midrange traumatic brain injuries (TBI) was the same as that after ponderosus traumatic brain injuries (TBI) . And there were significant difference .There were significant difference at the same time (2h , 6h , 12h , 24h , 48h and 72h) between light TBI and midrange TBI, between light TBI and ponderosus TBI , and between light TBI and ponderosus TBI after traumatic brain injuries (TBI()P<0.01). There were no significant difference at the same time (0.5h )between light TBI and midrange TBI, between light TBI and ponderosus TBI , and between light TBI and ponderosus TBI after traumatic brain injuries (TBI) (P>0.05).Conclusion: The AQP4mRNA was expressed in injured region of brain tissue during the stage of traumatic brain injury (TBI) in rats . And the expression was more stronger, complying with the progress of pathogenetic condition . We can make a conclusion: The expression of AQP4mRNA correlated closely with the level of traumatic brain injuries (TBI) . And AQP4 participates in the formation of traumatic brain injuries (TBI) . And AQP4 plays a important role during the stage of traumatic brain injury (TBI) .