 lipocortins are structurally related , glucocorticoid - inducible proteins that inhibit phospholipase a2 ( pla2 ) , thereby reducing the liberation of arachidonic acid from phospholipids and so limiting the synthesis of eicosanoid inflammatory mediators . 
 this study is the first demonstration of one lipocortin , lipocortin 1 ( lc 1 ; 37 kda ) , in human lung lavage supernatants . in lavage fluid from healthy volunteers , a higher percentage ( greater than 70% ) of the detected lc 1 was in its native form , compared to that from patients with abnormal lungs . in patients ' lavage fluids , lc 1 was more likely to be partially degraded ( 34 kda ) . in abnormal bronchoalveolar lavage fluid ( balf ) , the more polymorphonuclear neutrophils ( pmn)/lavage , the lower the proportion of lc 1 in the native ( 37 kda ) form ( n = 7 pairs , rs = -0.8214 , p less than 0.05 ) . 
 furthermore , when balf cells were cultured and the harvested conditioned media incubated with pure human recombinant lc 1 , degradation of the 37 kda form increased with the percentage of pmn ( n = 10 pairs , s = -0.7200 after 1 hr ; n = 6 pairs , rs = -0.9241 after 6 hr ) . 
 these results suggest that factors released from the pmn are responsible for lc 1 degradation in man . when recombinant human lc 1 was incubated with human neutrophil elastase , the enzyme degraded lc 1 in a dose - dependent way , suggesting that neutrophil elastase may be one such factor . since pmns are ubiquitous at sites of inflammation , it is possible that lc 1 degradation is a permissive mechanism , which ensures that sufficient inflammation occurs to destroy the provocative stimulus 
 . 
 however , it is equally possible that , in some circumstances , the mechanism may be pathological and that the inactivation of lc 1 leads to chronic , uncontrolled inflammation.imagesfigure 3figure 4.figure 4 . 
Images