Expression of TLR2 mRNA (a) TLR4 mRNA (b) in porcine lung tissue. Pigs were administered LPS injection with or without continuous ACTH pretreatment. TNF-α protein level in serum was determine by ELISA. TLR, toll-like receptor 2; LPS, lipopolysaccharide; ACTH, adrenocorticotropine hormone. b-actin was chosen as a reference for normalization in the qPCR and Western blot analyses. Mean values with different letters (a, b, c, or d) are significantly different (P <0.05) from each other. n = 5-6.