1. The role of cytokines and other inflammatory mediators in the progression of ischemic brain injury is a new and exciting era of research. Evidence in support for a role for TNF alpha in this respect is emerging as evidence on de novo upregulation of TNF alpha following ischemia is now well established. 2. TNF alpha administered directly to the brain parenchyma elicits local microvascular injury in the form of pericapillary edema and leukocyte adhesion to cerebral capillaries. 3. TNF alpha administered into the cerebroventricular space prior to ischemia augment the extent of tissue damage and neurological deficits. 4. Specific and potent inhibitors of TNF alpha synthesis or TNF alpha receptors must be developed and tried to prove firmly a role for TNF alpha in ischemic brain injury.