POMC and progressive pseudorheumatoid arthropathy of childhood: The levels of CRH, ACTH, and CORT were obviously increased (CRH: F(4,25) = 40.58, P < 0.001, LSD test; ACTH: F(4,25) = 38.28, P < 0.001, LSD test; CORT: F(4,25) = 17.41, P < 0.001, LSD test, Fig. 2a, b and c), and level of 5-HT was markedly decreased in the sera of PPD models as compared to those of control mice (F(4,25) = 7.35, P < 0.001, LSD test, Fig. 2d).