KININ RECEPTORS IN HUMAN VASCULAR TISSUE - THEIR ROLE IN ATHEROMATOUSDISEASE

Using samples of many human blood vessels, obtained at autopsy and spe cific antibodies directed to peptide sequences of the kinin B1 and B2 receptors, we demonstrate the localisation of these receptors within t he human vascular system using standard immunolabelling techniques. In large elastic arteries and veins, kinin receptors are present only in the endothelial cells whereas in all muscular arteries and arterioles , these receptors are present in both the endothelial and smooth muscl e cells. The identification of kinin receptors in human blood vessels confirms that kinins may modulate both vascular permeability and contr actility. The incidental finding at histology, of patchy atheromatous disease in the coronary, femoral, vertebral and pericallosal arteries, assisted in elucidating the role of these receptors in the commonest disease affecting human blood vessels. Intense labelling for B1 recept ors was observed in the endothelial cells, foamy macrophages, inflamma tory cells and fibroblasts within the thickened intima of the plaque a s well as in smooth muscle cells of the underlying tunica media. Immun oreactive B2 receptors were also observed in these cells but with redu ced intensity. The intense immunolabelling of B1 receptors in these re gions suggest that these may be induced by atheromatous disease and ma y have therapeutic importance for the B1 receptor antagonists.