Effect of adrenomedullin on adhesion of rheumatoid and osteoarthritic fibroblast-like synoviocytes (RA-FLSs and OA-FLSs, respectively). RA-FLSs or OA-FLSs are incubated for 1 hour with or without 10-7 M adrenomedullin (AM) and seeded for 2 hours on 96-well plates coated with the ECM proteins. The number of adherent cells is assessed by using colorimetry. Bars indicate mean ± SEM. *P < 0.05; ***P < 0.0001. Results are given as the ratio of optical density (OD) in each condition over control OD without adrenomedullin and reported as mean ± SEM of three experiments (different donors) performed in quadruplicate. (a) Comparison of basal adhesion of RA-FLSs and OA-FLSs with vitronectin, fibronectin, and type I collagen. (b) Effect of 10-7 M AM on RA-FLSs and OA-FLSs adhesion to vitronectin, fibronectin, and type I collagen.