[Paper disk granuloma method for experimental granuloma in rats (author's transl)].
The paper disk granuloma (PDG) method is a newly devised procedure for the screening of antiinflammatory drugs and was compared with the cotton pellet (CP) method. Results obtained were as follows; in the CP method, formation of granuloma was observed on the 1st day after the implantation of CP. On the 3rd day, maximum weight, protein and nucleic acids in granuloma were observed. The granuloma produced by PDG method was too small to collect on the 1st day. Weight and protein content of granuloma reached the peak on the 2nd or 3rd day. With respect to nucleic acids, maximum amounts were found on the 6th day. The incorporation of 3H-uridine into RNA was increased in the early stage of the formation of granuloma in both methods. The maximum incorporation of 3H-thymidine into DNA was noted on the 2nd day in CP method, and on the 3rd day in PDG method. Development of granuloma in the PDG method was different from that in CP method with respect to the synthesis of DNA. Antigranuloma action of fluocinolone acetonide (FA) was more marked in the PDG method than in the CP method, suggesting that the PDG method is more sensitive for screening of antiinflammatory drugs. Granuloma produced by the PDG method was also prevented and therapeutically suppressed by certain non-steroidal antiinflammatory drugs. ED50 values of applied FA, phenylbutazone, and 3-o-phthaloxy glycyrrhetinate were 27 microgram/kg, 91 mg/kg, and 66 mg/kg, respectively.