Figure 10
Effect of adrenomedullin on cytokine mRNA expression linked to antigen-induced arthritis. Expression levels of TNFα, IL-6, transforming growth factor beta (TGFβ), and vascular endothelial growth factor (VEGF) mRNA in the infrapatellar fat pads were determined by real-time quantitative PCR. (a) Adrenomedullin (AM) treatment reduced TNFα mRNA expression in a dose-dependent manner. Daily intra-articular injections of 3 μg AM significantly suppressed the TNFα mRNA level by 21% and 49% at day 8 and day 21, respectively. (b) AM increased IL-6 mRNA expression in a dose-dependent manner. Daily intra-articular injections of 3 μg AM significantly increased the IL-6 mRNA level by 45% and 121% at day 8 and day 21, respectively. (c) AM treatment did not alter the TGFβ mRNA level. (d) Although the VEGF mRNA level was suppressed by 10% at 3 μg AM on day 8, a dose-dependent effect of AM on VEGF mRNA expression was not observed. Open and closed columns represent the data at day 8 (n = 5 in each group) and day 21 (n = 3 in each group), respectively. Data expressed as the mean ± standard error of the mean. *P < 0.05 and **P < 0.01, compared with contralateral knees