Figure 8

Biological activity of TNFα in transgenic rat brain shown by TRADD protein expression. This bar graph shows expression of TNF receptor-associated protein death domain (TRADD) protein in brain homogenates obtained from TNFα-transgenic (TNFα-Tg) and non-Tg rats. Samples were obtained after 3 hours of reperfusion following one hour of focal cerebral ischemia. TRADD protein expression is shown as mean ± SD optical density units measured from digitized electrophoretic bands. In ischemic TNFα-Tg brain, TRADD protein was expressed more intensely within the border zone approximating the ischemic penumbra (n = 5 per group; p ≤ 0.01; ANOVA/Fisher's test) and in the developing infarct core (p ≤ 0.05; ANOVA/Fisher's test) when compared to non-Tg littermates. TRADD was also elevated significantly in the normally-perfused hemisphere (control) of the TNFα-Tg rat compared to non-Tg animals (p ≤ 0.01; ANOVA/Fisher's test), reflecting increased constitutive expression of protein in response to interaction between active, soluble TNFα and its p55/TNFR1 receptor. There were no significant differences between TRADD protein expression in the normally-perfused hemisphere and the ischemic border zone or infarct core in TNFα-Tg rats (p = NS). *p ≤ 0.05; **p ≤ 0.01