Figure 3. Methane suppressed activation of inflammatory cytokine. The blood samples were collected 12 and 24 h after the cecal ligation and puncture (CLP) (n = 12). The levels of serum (A) tumor necrosis factor (TNF)-α and (B) interleukin (IL)-6 were detected by ELISA. The supernatant of RAW 264.7 cells and primary peritoneal macrophages was collected 24 h after lipopolysaccharide+ adenosine-triphosphate (LPS + ATP) stimulation (n = 3). The levels of (C) TNF-α and (D) IL-6 in supernatant were detected by ELISA. (Data are shown as the mean ±SD. *P < 0.05; **p < 0.01; ***P < 0.001; #P < 0.05 versus normal medium (NM) group; $p < 0.05 versus methane-rich medium (MRM) group; &P < 0.05 versus. normal medium+ lipopolysaccharide+ adenosine-triphosphate (NM+L+A) group).