Changes in TNF-α antigen in plasma by stress and effects of anti–TNF-α antibody on the stress-induced TF mRNA expression.

TNF-α antigen levels in plasma of 8-week-old (8w) and 24-month-old (24m) mice (A) and of 6-week-old obese and lean mice (D) before (■) and after (▪) 20 hours of restraint stress were determined by enzyme-linked immunosorbent assay (*P < .04; **P < .01; ***P < .005). In separate experiments, the mice were pretreated either with control or with anti–TNF-α antibody (25 μg/mouse or 1 μg/g) and then subjected to 20 hours of restraint stress. Kidneys, adipose tissues, or livers were harvested and analyzed for TF mRNA by quantitative RT-PCR (young and aged mice, B and C; obese and lean mice, E and F). ■ indicates no stress; ▪, pretreated with control antibody; ▨, pretreated with anti–TNF-α antibody. The data are expressed as the means and SD (n = 6). Statistical significances were analyzed between the groups of pretreatment with control antibody and with anti–TNF-α antibody in each tissue (*P < .05; **P < .02).