IL-1 AND IFN-GAMMA INCREASE VASCULAR-PERMEABILITY

  • 1 June 1988
    • journal article
    • research article
    • Vol. 64  (2) , 301-305
Abstract
We examined the effect of cytokines on vascular permeability in vivo. Wistar rats received intradermal injections of various cytokine preparations and the permeability index (.DELTA.PI) was calculated from the difference between the absorption values of cytokine- and vehicle-treated skin sections after the extraction of accumulated Evans blue vital dye. Injections of a mixture of recombinant interleukin-1.alpha. and .beta. (Il-1.alpha., IL-1.beta.) and interferon-gamma (IFN-.gamma.) caused a maximal increase of permeability after 30 min (.DELTA.PI = 2). The administration of single recombinant cytokines revealed that the increase of permeability is mainly due to the action of IL-1.beta. (.DELTA.PI = 1.4) and IFN-.gamma. (.DELTA.PI = 2.9) (P < 0.001) at doses of 1-20 .mu.U per injection site. IL-1.alpha. slightly increased vascular permeability, whereas recombinant IL-2 and recombinant tumour necrosis factor .alpha. had no significant effects. Histological observations revealed significantly increased numbers of degranulated mast cells in skin sections pretreated with IL-1.beta. (P < 0.005) or IFN-.gamma. (P < 0.001). The cytokine-mediated rise of vascular permeability could be suppressed by pretreatment of the animals with the vasoactive amine antagonizing drugs methysergide, pizotifen and cyproheptadine. Our experiments indicate an important role of IL-1.beta. and IFN-.gamma. as vasoactive substances besides their function as hormone-like messengers between leucocytes.