The secretion of glucocorticoids is a classic endocrine response to stress. Despite that, it remains controversial as to what purpose glucocorticoids serve at such times(1).Many me-chanismsms of glucocorticoids action remain elusive.The classical model for glucocortico-id action relies on the interaction of the steroid with an intracellular receptor that modulates transcriptional activity of target genes.This signaling route for glucocorticoids is well cha-racterized and accounts for many of the known effects of steroid hormones.However, some effects are too rapid,appear to utilize mechanisms involving membrane receptors and se-cond messengers(2).Several reviews focus on steroid membrane receptors and nongeno-mic actions of steroids(3).The detailed mechanisms of these nongenomic actions are still unclear, membrane-bound glucocorticoid receptors have been suggested to be involved, although their phisiological existence in humans so far is hypothetical(4).In this study we de- monstrated in porcine human peripheral blood mononuclear cells obtained from healthy blood donors the presence of a membrane glucocorticoid binding sitesusing connection of cells with the glucocrticoid fixed covalently on a inert carrier incapable to penatrate inside a cell (Triamcinolone-Sepharose).The kinetics of connection cells