EFFECT OF HYPOCHLORITE (HOCL)-MODIFIED LOW-DENSITY LIPOPROTEINS AND HIGH-DENSITY-LIPOPROTEINS ON PLATELET-FUNCTION

As hypochlorous acid (HOCl) might be a potential candidate for generat ion of modified (lipo)proteins in vivo, the present study was aimed at investigating the effects of HOCl-modified lipoproteins on platelet f unction in vitro. Lipoproteins modified with HOCl at concentrations th at occur physiologically did not induce spontaneous platelet aggregati on. However, low density lipoproteins (LDL; 100 to 500 mu g protein/ml ) increased platelet aggregation and fluorescence anisotropy in respon se to ADP (1 and 10 mu M) and thrombin (0.1 and 0.5 U/ml) as well as m alondialdehyde (MDA) formation as a function of increasing HOCl-concen trations (0.2 to 1.6 mM). HOCl-modified high density lipoprotein subfr action 3 (HDL3) had no effect on platelet function.