Heterogeneity of human platelets. II. Functional evidence suggestive of young and old platelets.
In the previous communication, suggestive evidence was presented for large-heavy platelets being "young" platelets and light-small platelets being "old" platelets. Large-heavy, light-small, and total human platelet populations were compared with respect to their platelet function. After addition of adenosine diphosphate (ADP), thrombin, or epinephrine, platelet aggregation time was 3.0-, 4.5-, and 3.3-fold shorter with large-heavy platelets compared with light-small platelets, and large-heavy platelets released 3.7-, 7.6-, and 8.1-fold greater adenosine triphosphate (ATP) into the medium, respectively, than did light-small platelets. After platelet aggregation by thrombin or epinephrine, large-heavy platelets released 6.0- and 3.8-fold more ADP into the medium than did light-small platelets. After platelet aggregation by ADP, light-small platelets consumed 5.9-fold greater added extracellular ADP than did large-heavy platelets.Large-heavy platelets aggregated by ADP, thrombin, or epinephrine released 9.1-, 8.5-, and 12.7-fold greater platelet factor 4 than light-small platelets similarly treated.
D000227:Adenine Nucleotides / Q000378:metabolism / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000378:metabolism; D001779:Blood Coagulation Factors / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D002499:Centrifugation, Density Gradient; D004837:Epinephrine / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D013917:Thrombin / Q000494:pharmacology
D000227:Adenine Nucleotides; D001779:Blood Coagulation Factors; D000255:Adenosine Triphosphate; D013917:Thrombin; D004837:Epinephrine