Opposing Effects of Platelet-Activating Factor and Lyso-Platelet-Activating Factor on Neutrophil and Platelet Activation

Opposing effects of platelet-activating factor and lyso-platelet-activating factor on neutrophil and platelet activation.

Platelet-activating factor (PAF) is a potent, bioactive phospholipid that acts on multiple cells and tissues through its G protein-coupled receptor (GPCR). PAF is not stored but is rapidly generated via enzymatic acetylation of the precursor 1-O-hexadecyl-2-hydroxy-sn-glycero-3-phosphocholine (lysoPAF). The bioactivity of PAF is effectively and tightly regulated by PAF acetylhydrolases, which c...

The effect of platelet activating factor on the motility and acrosome reaction of ram spermatozoa

Platelet activating factor (PAF) is a novel signaling phospholipids that in addition to platelet activation has many biological properties. The acrosome reaction, as an essential step in mammalian fertilization, can occur in response to several agents such as PAF. Therefore, the present study aimed to assess the effect of PAF on the motility and acrosome reaction of ram spermatozoa. Semen was c...

Platelet activating factor revisited.

Platelet-activating factor.

Platelet-activating factor is a phospholipid with diverse potent physiological effects. Its actions are achieved at concentrations as low as IO-‘” M in some systems and almost always by lo-’ M as an intercellular messenger. The molecular structure of PAF was discovered through parallel investigations of two different biological activities: a factor in the blood of rabbits undergoing anaphylaxis...

Platelet-activating factor.

Our ability to chemically characterize and synthesize this autacoid of allergy and inflammation has given us a unique opportunity to study these important molecules in a highly disciplined fashion. It has also opened the door to a vista of research approaches to define PAF's normal physiologic role as well as its actions as an immunopathologic mediator. Recent work is described.