PLATELET AND PLASMA PLATELET-ACTIVATING-FACTOR IN SEPSIS AND MYOCARDIAL-INFARCTION

Platelet-activating factor (PAF) is a potent phospholipid mediator whi ch has been implicated in the pathophysiology and complications of div erse clinical illness such as myocardial infarction and shock. 10 norm al males, 13 presenting with acute myocardial infarction and 13 with c linical sepsis were studied. In myocardial infarction, plasma PAF, pla telet PAF receptor number and platelet-associated PAF were not signifi cantly different from normal. In clinical sepsis, plasma PAF was not d ifferent and platelet-associated PAF was slightly, but not significant ly, higher. Similarly, in this group, the production of PAF from resti ng and stimulated neutrophils was not different from normal. Despite s ignificant experimental evidence from animal studies for the involveme nt of PAF in cardiovascular disorders, this clinical study provides li ttle direct evidence to support this view. Our results suggest that PA F is maintained at a relatively constant circulating level, a conseque nce of metabolic regulation and a high avidity for platelets and neutr ophils.