Effect of hyperbaric oxygen on the permeability of the blood-brain barrier in rats with global cerebral ischemia/reperfusion injury

Objective: The aim of this study was to investigate the effects of hyperbaric oxygen on the permeability of the blood-brain barrier in rats with global cerebral ischemia/reperfusion injury and explore possible mechanisms. Methods: A rat model of global cerebral ischemia/reperfusion injury established via Pulsinelli four-vessel occlusion method and a total of 162 Wistar rats were randomly divided into three groups, including sham group, global cerebral ischemia/reperfusion group (IR group) and hyperbaric oxygen treated group (HBO group). Permeability of the blood-brain barrier of these rats were evaluated by Evans Blue staining. The expression of caveolin-1 and tight junction protein ZO-1 was examined by Immunohistochemistry staining and western-blotting. Results: Successfully establishment of the rat model was verified by W:D ratio, and significantly increased Evans Blue level was found in IR group compared to control group, whereas hyperbaric treatment could result in decreased Evans Blue level in HBO group. Increased expression of caveolin-1 and tight junction protein ZO-1 were found in rats with hyperbaric oxygen exposure compared to those in IS group. Conclusions: Hyperbaric oxygen exposure improved the permeability of the blood-brain barrier in rats with global cerebral ischemia/reperfusion injury, and increased expression of caveolin-1 and tight junction protein ZO-1 were involved in the mechanisms.