The Functional Roles of Constitutively Active Calcineurin in Delayed Neuronal Death after Brain Ischemia

Phagocytosis executes delayed neuronal death after focal brain ischemia.

Delayed neuronal loss and brain atrophy after cerebral ischemia contribute to stroke and dementia pathology, but the mechanisms are poorly understood. Phagocytic removal of neurons is generally assumed to be beneficial and to occur only after neuronal death. However, we report herein that inhibition of phagocytosis can prevent delayed loss and death of functional neurons after transient brain i...

Involvement of MMPs in delayed neuronal death after global ischemia.

Spatial and temporal relations between metalloproteinase (MMP-2 and MMP-9) activation and laminin degradation in gerbil hippocampus after transient cerebral ischemia has been studied. Activity of MMPs was determined by gelatin zymography in homogenates from dorsal (DP, an equivalent of CA1 sector) and abdominal (AbP, containing CA2-4 and gyrus dentatus) parts of hippocampus. A significant activ...

Absence of Delayed Neuronal Death in ATP-Injected Brain: Possible Roles of Astrogliosis

Although secondary delayed neuronal death has been considered as a therapeutic target to minimize brain damage induced by several injuries, delayed neuronal death does not occur always. In this study, we investigated possible mechanisms that prevent delayed neuronal death in the ATP-injected substantia nigra (SN) and cortex, where delayed neuronal death does not occur. In both the SN and cortex...

Timing of Hypothermia (During or After Global Cerebral Ischemia) Differentially Affects Acute Brain Edema and Delayed Neuronal Death

Ca2+ signals and neuronal death in brain ischemia.

Although Ca(2+) signals are necessary for cell communication and survival, abnormal cellular Ca(2+) load can trigger different cell death programs. Ca(2+) mediates cell death by activating proteases (ie, calpains), by reinforcing signals leading to caspase activation or by triggering other catabolic processes mediated by lipases and nucleases. Failure in the clearance of excitatory amino acid i...