Apoptotic death in cortical neurons of mice subjected to focal ischemia

Permanent focal cortical ischemia was induced in mice by electrocoagulation of the middle cerebral artery. At different time intervals after the injury, the volume of infarction was assessed together with any analysis of neuronal death. Morphological studies of ischemic brains and detection of nucleosomal DNA ladder within ipsilateral cortices might implicate a component of this neuronal loss to apoptosis as well as necrosis. Furthermore, we used the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-boitin nick end labelling) procedure to detect in situ DNA fragmentation. The localization and the proportion of apoptotic cells in the ischemic mouse brain would indicated that apoptosis contributes largely to the cellular loss induced by cerebral ischemia.