Early increases in TNF-alpha, IL-6 and IL-1 beta levels following transient cerebral ischemia in gerbil brain

The effects of transient global ischemia using bilateral carotid artery occlusion on regional cytokine levels in gerbil brain were investigated using enzyme-linked immunoassay techniques. Brain concentrations of interleukin-6 (IL-6), interleukin-1 beta (IL-1 beta), and tumor necrosis factor-alpha (TNF-alpha) were increased during the early recirculation period (<6 h) after 10 min of ischemia, with lesser degrees of elevation following only 5 min of ischemia. TNF-alpha levels in the hippocampus and striatum were significantly increased as early as 1 h after recirculation, declining sharply to control levels by 12 h, then transiently increasing at 24 h. Elevated levels of IL-1 beta and IL-6 were not seen until 3-6 h post-occlusion. No significant increases in cytokine concentrations were observed in the cerebellum or thalamus. These results suggest that regionally selective increases in cytokines may be involved in the pathophysiological changes in hippocampus and striatum following transient cerebral ischemia.