Platelet aggregation evoked in vitro and in vivo by phosphatidic acids and lysoderivatives: identity with substances in aged serum (DAS)

Thromb Haemost. 1979 Aug 31;42(2):631-40.


In serum incubated at 36 degrees C for 18-24 hours a factor (DAS) develops which on intravenous injection into cats evokes platelet aggregation followed by an increase in pulmonary vascular resistance (PVR). This change in PVR is mediated via the platelets since it significantly correlates with the preinjection platelet count. There is evidence that phosphatidic acids (PA) and lysophosphatidic acids (LPA) are the active components of DAS. Investigations performed on platelet-rich plasma from man, cat, pig, dog, rabbit, guinea pig, and rat demonstrate that only human and feline platelets exposed to PA or to LPA are aggregated. Feline platelets are more sensitive to either compound than are the platelets from men; however, human platelets exhibit two exceptional properties, a) the sensitivity rapidly declines with time, b) pretreatment with subthreshold concentrations of LPA or PA induces a specific tachyphylaxis.

MeSH terms

  • Adenosine Diphosphate / pharmacology
  • Aging*
  • Animals
  • Blood
  • Cats
  • Depression, Chemical*
  • Dogs
  • Edetic Acid / pharmacology
  • Female
  • Guinea Pigs
  • Humans
  • Lysophosphatidylcholines / pharmacology
  • Male
  • Phosphatidic Acids / pharmacology*
  • Platelet Aggregation / drug effects*
  • Rabbits
  • Rats
  • Swine
  • Tachyphylaxis
  • Tissue Extracts / pharmacology
  • Vascular Resistance


  • Lysophosphatidylcholines
  • Phosphatidic Acids
  • Tissue Extracts
  • Adenosine Diphosphate
  • Edetic Acid