Experimental Research Of The Inflammatory Reaction And Therapeutical Effect Of Hyperbaric Oxygen Following Traumatic Brain Injury In Rat

Objective: We expected to research the effects of inflammatory cytokines (TNF-alpha, IL-6, IL-8 and IL-10) in second brain injury by detecting the levels of these cytokines in brain tissue and serum of rats suffering from traumatic brain injury(TBI). We want to explore the effects and mechanisms of hyperbaric oxygen(HBO) on rat with TBI through observing the changes of these cytokines in brain tissue and serum after the therapy of HBO.Methods: (1)The model of severe brain injury were created by gas percussion. (2) Rats were treated by HBO. (3)The histological changes were observed by HE staining. (4) The levels of inflammatory cytokines (TNF-alpha, IL-6, IL-8 and IL-10)in brain tissue and serum of rats weredetected by radioimmunoassay(RIA).Results:1. TNF-alpha, IL-8 and IL-10 significantly increased at 3h in brain tissue and serum, IL-6 ascended at 24h in brain tissue and 3h in serum after TBI. TNF-alpha, IL-6, IL-8 and IL-10 kept on high level to 168h and peaked at 168h, 168h, 72h, 24h respectively in rats' brain tissue and at 120h, 72h, 3h, 168h respectively in serum following TBI.2. TNF-alpha, IL-6, IL-8 and IL-10 in brain tissue were statistically higher than that of in serum (P<0.01), and they were all linear positive correlation (r=0.791 P<0.01; r=0.563 P<0.01; r=0.525 P<0.01; r=0.459 P<0.01 respectively) between brain tissue and serum.3. Every one of the inflammatory cytokines in TBI brain tissue and serum decreased after treatment with HBO. IL-6 in serum began significantly reduced at 3h. TNF-alpha in brain and serum and IL-10 in brain began statistically decreased at 24h. IL-6 in brain and IL-10 in serum markedly reduced at 72h after TBI.Conclusions:1. The inflammatory cytokines in brain tissue and serum reactively increased in early period after TBI, and continually increased to 168h. Inflammatory cytokines participated in the processes of SBI and caused the disorder of the immune balance.2. HBO showed protective effects by regulating the levels of inflammatory cytokines and relieving the second injury caused by the inflammatory cytokines of brain tissue and serum in rats after TBI.3. Accelerating to restore the balance of the post-trauma stress disorder, improving tissular hypoxia-ischemia, inhibiting the activation of inflammatory cells and the synthesis and release of inflammatory cytokines were the possibly therapeutic mechanisms of HBO on TBI.