INCREASED INTRAARTICULAR SUBSTANCE-P AND PROSTAGLANDIN-E2 FOLLOWING INJECTION OF INTERLEUKIN-1 IN RABBITS

  • 1 January 1990
    • journal article
    • research article
    • Vol. 12  (1) , 11-14
Abstract
Inflammation was induced by intra-articular injection of 100 ng recombinant human interleukin-1.alpha. (rhIL-1) into rabbit knees. Substance P (SP) and prostaglandin E2 (PGE2) were measured by radioimmunoassay (RIA) in the joint fluid at 4, 24 and 48 h after rhIL-1 injection. SP was increased by 4h, further increased at 24 h and remained elevated at 48h. PGE2 concentration was highest at 4h and remained elevated at 48h after rhIL-1 injection. Because of the proinflammatory activities of SP and PGE2, our studies suggest that the elevated SP and PGE2, in the joint may amplify or sustain an initial receptor-mediated inflammatory response to IL-1.