Objective      To determine the protective effects of perfluorooctyl-bromide (PFOB) nanoparticles on early brain injury (EBI) in rats following subarachnoid hemorrhage (SAH).       Methods      Ninety male healthy SD rats were randomly divided into 3 groups

that is

sham-operation group (n=30)

SAH model group (n=30) and SAH+PFOB group (n=30). Rat SAH model was produced by injecting blood into the prechiasmatic cistern. PFOB nanoparticles as emulsifier with high concentrations of dissolved oxygen was injected to the rats of the treatment group via tail vein in 3 h after model establishment. Brain water content was measured in 24 h after surgery. Morphological changes in the rat hippocampal CA1 region were examined by transmission electron microscopy. The neuronal apoptosis in the region was determined by TUNEL assay

and immunohistochemical staining was performed for the expression of Caspase-3. Protein expression levels of Caspase-3 were detected by Western blot assay in 12

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48 and 72 h postoperatively.       Results      Compared to the SAH group

the SAH+PFOB group had significantly lower brain water content (P0.01). Transmission electron microscopy revealed the reduction of neuronal apoptosis

alleviation of glial cell swelling

and mitigation of perivascular edema in the hippocampal region. Immunohistochemical data showed that the expression of apoptosis-related factor Caspase-3 was significantly reduced. TUNEL staining showed that neuronal apoptosis was significantly reduced in the hippocampal CA1 region (P0.01). Western blot assay indicated that the expression of Caspase-3 was significantly reduced at 12

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48 and 72 h after SAH (P0.01).       Conclusion      PFOB nanoparticles with high oxygen content could counteract ischemia and hypoxia

block neuronal apoptotic pathways

reduce neuronal apoptosis

and achieve neuroprotective effects in EBI following SAH.