The effect of systemic heparinisation and haemodialysis on plasma octadeca-9,11-dienoic acid (9,11-LA').

Systemic heparinisation induces a sharp rise not only in plasma total free fatty acids but also in 9,11-LA' concentration and in the 9,11-LA'/9,12-LA molar ratio. This "heparin effect" is enhanced by haemodialysis with cuprophan membranes but not with polycarbonate membranes.