Summary
When exogenous adenosine monophosphate (AMP) and diphosphate (ADP) were added to sonicated
platelet-rich human blood plasma in AMP-ADP ratio approximating that normally present
in platelets, a ratio close to 1.0 was consistently established within 20 to 60 minutes
of incubation at 37° C. This resulted both from progressive disappearance of ADP and
from initial augmentation followed by disappearance of AMP, the disappearance of ADP
always being greater however than the disappearance of AMP so that the higher ratio
was maintained.
AMP appeared as ADP disappeared during the first 20 minutes of incubation. Platelet
adenylate kinase, plasma 5-adenylic acid deaminase and nonspecific alkaline phosphatases
appeared to be of particular importance in achieving the changing ratios of nucleotides.