OBJECTIVETo investigate the effects of hyperbaric oxygen (HBO) treatment on the activation of astrocytes and the expression of glia-derived neurotrophic factor (GDNF) and nerve growth factor (NGF) in the brain after traumatic brain injury (TBI).

METHODS54 male SD rats were randomly divided into three groups (n = 18): sham-operated, TBI and HBO treatment groups. TBI was induced with Feeney's method, bone window was opened without strike on the brain tissue in the sham-operated group. HBO group rats received HBO treatment for 60 min in the hyperbaric chamber containing O2 100% at 3 ATA. When neurological functions were measured 48 h after TBI, rats were decapitated, the brain water content of 18 rats was measured, 18 brains were sliced for the morphological observation after Nissl staining and for the immunohistochemistry staining of astrocyte markers glial fibrillary acidic protein (GFAP), vimentin and S100, and the other 18 brains of injured side were used for Western blot analysis of GDNF and NGF.

RESULTSHBO treatment reduced the neurological deficit, brain water content and hippocampal neuronal loss. In the observed cortex and hippocampal area astrocytes were activated, the cell number of positive expression of astrocyte markers GFAP, vimentin and S100 was increased, and the expression of GDNF and NGF was elevated after TBI. However, these indices were all enhanced further after the HBO treatment.

CONCLUSIONIt is suggested that HBO may be an effective therapy for TBI and upregulation of the expression of GDNF and NGF may underly the effect of HBO.