ABSTRACT
This chapter provides an overview of cellular responses by all of the cell types found within the brain. There is a differential astrocyte response depending upon whether the ischaemic insult is long or severe enough to result in irreversible or reversible neuronal injury. There is good evidence that both smooth muscle of the tunica media and the endothelium of the brain microvasculature respond rapidy to an ischaemic or other type of brain insult. It is also clear that there is a wide sprectrum of susceptibility to ischaemic insult by neurons in different regions of the brain. In both types of ischaemic injury, swollen astrocytic processes extend through both the ischaemic core and for a considerable distance into the otherwise morphologically intact neuropil surrounding the ischaemic lesion. Such astrocytic swelling probably results in a decrease in the extracellular space which has been documented in both ischaemia and spreading depression and contusion injury to the human cerebral cortex.
