Abstract #0618

Denes A, Vidyasagar R, Feng J, Nrvinen J, McColl B, Kauppinen R, Allan S

Macrophages are detected in vivo by MRI using AMI-227. Macrophage invasion and microglial activation are known to happen in acute stroke, yet contribution of these cells to infaction process is not clear. Here, mice were subjected to 30 minutes middle cerebral artery occlusion, injected daily with AMI-227/Magnevist and monitored daily for infarct evolution. Histology showed that resident microglia become rapidly activated, proliferated and phagocytosed neutrophils, while only a small infiltrating exogenous macrophage population was observed by 72 hours. Thus, blood-borne macrophages are not profoundly involved in the development of ischaemic infarction in this experimental model.