Heterogeneity of human Platelets: I. Metabolic and kinetic evidence suggestive of young and old platelets

• Text
• PDF

Abstract

Human platelets have been separated into two extreme density populations by centrifugation in specific density media. A large-heavy platelet population with specific gravity > 1.055 and a light-small population with specific gravity < 1.046 were obtained, each representing approximately 15-20% of the total population volume. The average volume per platelet of the separated large-heavy and light-small platelet populations was 12 and 5 μ3 respectively. When data are expressed per milliliter platelets or per gram wet weight, the large-heavy platelet population had a 2-fold greater glycogen content, 1.3-fold greater orthophosphate content, 1.3-fold greater total adenine nucleotide content, 4.2-fold greater rate of glycogenolysis, 2.6-fold greater rate of glycolysis, 2.9-fold greater rate of protein synthesis, and 5.7-fold greater rate of glycogen synthesis. Significant differences were not obtained with respect to total lipid content or total lipid synthesis. The large-heavy platelet had a 2.5-fold greater resistance to osmotic shock as measured by adenosine triphosphate (ATP) or adenosine diphosphate (ADP) release.

Authors

Simon Karpatkin, Arthur Charmatz