Effects of LPS/ACTH on serum TNF-α concentration. Pigs were administered LPS injection with or without continuous ACTH pretreatment. TNF-α protein level in serum was determine by ELISA. TNF-α, Tumor necrosis factor; LPS, lipopolysaccharide; ACTH, adrenocorticotropine. Mean values with different letters (a, b, c, or d) are significantly different (P <0.05) from each other. n = 5-6.