Fig. 5

Effects of 5-hydroxytryptophan (5-HTP) on the expression of cyclooxygenase-2) (COX-2 and prostaglandin E₂ (PGE ₂ ) in activated splenocytes and mice with collagen-induced arthritis (CIA). a mRNA levels (mean ± SD) of COX-2 in activated splenocytes. b Protein levels of COX-2 and PGE₂ receptor EP-2 in activated splenocytes. N.D. undetectable. exp 1 and exp 2 experiment 1 and 2. c and d PGE₂ levels (mean ± standard error) in the culture supernatants and mice serum. *Significant compared with no 5-HTP treatment cells (a and c) or group 1 (d). The grouping (d) was as described in Fig. 3a. At least six mice in each group were studied (d). Multiple comparisons were performed using the Kruskal–Wallis test, if significant (p <0.05), then the Duncan test was used to find out which pairs were different