Interleukin-1 induced vascular pathology "in vivo": a scanning electron-microscopy study.

Ethylene vinyl acetate (EVA) discs containing either 50 U interleukin-1 (IL-1) or 250 mg bovine serum albumin as control were implanted around the exposed jugular veins of rabbits. After 24 hr, the veins were examined by scanning electron-microscopy. Compared with minor changes in control vein lumena, those of EVA-IL-1 treated veins showed extensive endothelial cell denudation and exposure of basement membrane associated with platelet accumulation and adherence/subendothelial migration of leucocytes. These observations suggest that locally-released IL-1 provokes significant vascular pathological changes "in vivo" and emphasise the importance of this cytokine as a mediator of inflammatory and thrombotic/atherosclerotic diseases.