동물모델에서의 급성통풍발작 유발인자와 조직학적 변화

Abstract

Objective: To see whether monosodium urate(MSU) crystals can complex ferric iron in vivo, and to compare the histologic inflammatory reaction to MSU with or without iron in the rat animal model. Methods: MSU crystals were synthesized and tested to be able to complex iron in vitro. MSU crystals which were confirmed to be able to complex iron in vitro were encapsulated and put in diffusion chambers made with discs and filters. They were implanted in 6 rats. The chambers were retrieved 24 hours later, and the concentration of iron associated with the urate was measured by using inductively coupled plasma emission spectroscopy. In order to compare the histologic inflammatory reaction to MSU with or without iron in the rat animal model, one group with 25mg MSU crystals suspended in 5ml phosphate buffered saline(PBS) and the other with 2Smg MSU crystals in 5ml of 5mM ferric chloride PBS were injected into 6-day-old air pouch model in rats. Pouch tissue specimen were collected from 5 rats at 6, 24 and 48 hours in two groups. Various histologic findings were graded and compared by two blinded observers using a 0-3 point scale(normal, minor, moderate and severe abnormalities). Results: The MSU crystals picked up ferric iron in vivo(8.7±1.8μmoles/g). On histologic evaluation, there were more pouch wall inflammatory cells in MSU plus iron group than MSU group at 48 hours(p<0.015). Conclusions: In MSU crystal-induced acute gouty inflammation, MSU crystals were confirmed to complex with iron in vivo. Histologically, the complexation of iron with MSU crystals showed increased inflammatory reaction in vivo. Iron may increase inflammatory response in acute gouty inflammation.