Objectives To investigate dynamic changes of complement regulatory protein CD46 expression and discuss its possible mechanisms. During cerebral ischaemia-reperfusion injury.

Methods The middle cerebral artery occlusion (MACO) model was induced through filament method. Brain Pathological injury was recorded. Immunofluorescence and real time RT-PCR method were used to detect complement regulatory protein CD46 expression.

Results Brain pathological injury was the most serious at 24 h after reperfusion, The complement regulatory protein CD46 expression decreased gradually after local cerebral ischaemia-reperfusion injury, the lowest at 24 h after reperfusion, and returned to normal at 96 h after reperfusion.complement regulatory protein CD46 expression was negative correlated with brain pathological injury.

Conclusions The complement regulatory protein CD46 has a significant change after cerebral ischaemia-reperfusion, it was speculated that participate in the course of the injury after ischaemia-reperfusion, So inhibition of complement by complement regulatory protein CD46 is likely to be a new important method of treatment.