Significance of analyses of inflammatory reactions in inflammatory models

Abstract

Inflammatory models are used for several purposes. Screening of new anti-inflammatory agents is one of the main purposes and the models are commonly used in routine work. For analyses of diseases through inflammatory models and development of new therapy, the models such as rat paw edema, arthrus reaction, Masugi nephritis, adjuvant arthr itis, are useful, but one should realized that one model cannot cover the whole process of one disease and a certain model may simulate a certain phase of the inflammatory process of a disease.Rheumatoid arthritis is known to be a chronically progressing, proliferative inflammation. In an acute exacerbation phase of the disease, however, plasma kallikrein-kinin system is activated insinovial fluid with signs of acute inflammation. Even in an acute exudative inflammation, such as rat carrageenin-induced pleurisy, mediators which appear in exudate are different from time to time. In the pleurisy, 6-keto-PGF1α, PGE2 and TXB2 appeared successively in the pleural fluid in the first 1-7hr after carrageenin and PGE2 played the min role in exudation. Plasma kallikreinkinin system also took more important part in an accumulation of the pleural fluid. Thus, analyses of inflammatory models are necessary for development of therapeutic drugs and selection of suitable period in administration of anti-inflammatory agents.