Effect of ultra early hyperbaric oxygen treatment on the permeability of blood-brain barrier in persistent cerebral ischemic rats

Objective To explore the effect of ultra early hyperbaric oxygen (HBO) treatment on the permeability of blood-brain barrier in persistent cerebral ischemic rats. Methods 66 healthy SD rats were randomly divided into 11 groups: i. e. the sham surgical group, the cerebral ischemia for 2, 4, 6, 12, 24 hours groups and the HBO treatment for 2, 4, 6, 12, 24 hours groups, each consisting of 6 rats. The rat model of middle cerebral artery occlusion (MCAO) was developed in the rats of the cerebral ischemia groups and the HBO groups by Longa suture method. Ten minutes after development of the model, the rats in the HBO groups received HBO treatment at a pressure of 0.2 MPa (2.0 ATA) for one hour. The severity of blood-brain barrier damage in the rats of the groups was measured by Evans blue extravagating experiment. Results The permeability of blood-brain barrier reached peak at hour 4 in the rats of the cerebral ischemia group(6.15±1.81). As compared with that of the cerebral ischemia group(6.15±1.81, 4.64±0.71), the permeability of blood-brain barrier in the rats of the HBO group(3.84±1.26, 3.27±0.28) decreased most significantly at hour 4 and hour 12, and there was statistical significance when comparisons were made between the groups(P<0.05). Conclusion Ultra early HBO treatment could reduce the permeability of Evans blue extravasation in the brain tissue of the rats with persistent cerebral ischemia, improve blood-brain barrier permeability and protect the blood-brain barrier. The permeability decreased most significantly in the cerebral ischemia rats at hour 4 and hour 12. Key words: Ultra early; Hyperbaric oxygen treatment; Persistent cerebral ischemia; Blood-brain barrier; Permeability