Automated quantification of rat plasma acute phase reactants in experimental inflammation.

Methods are described for the quantification of certain acute phase reactants (albumin, iron, fibrinogen, seromucoid, haptoglobin, and ceruloplasmin) in small amounts of plasma using the COBAS-BIO centrifugal analyzer. These methods have been applied to determine the concentrations of these acute-phase reactants (APRs) in rat plasma during the first 5 days of adjuvant-induced arthritis. The levels of the APRs alter with the degree of inflammation in a dose-related manner. Administration of the antiinflammatory and antirheumatic drugs (indomethacin, dexamethasone, and clobuzarit [CLOZIC]) during the course of the adjuvant-induced arthritis reduced the inflammatory response as judged by the measurement of oedema. These compounds, however, show differential effects on the profile of APRs as systemic measurements of the inflammatory disease. The present study shows that specific classes of drug have defined effects on acute-phase protein concentration. We believe that the multiple analysis of APR levels during the course of inflammation may help to distinguish between and elucidate the mechanisms of action, of antiinflammatory and antirheumatic drugs.