Summary
Platelet aggregation and adenine nucleotides in platelets have been studied in thirteen
patients with myeloproliferative disorders. ADP induced aggregation was abnormal in
two patients, but collagen induced aggregation was impaired in 11 patients. The concentrations
of ATP and ADP in resting platelets in the patients with abnormal aggregation were
significantly less than those in normal subjects. Marked reduction of the amounts
of both nucleotides released into plasma was also observed after stimulation of collagen
in these patients. Platelets in the patients with normal functions contained almost
normal amounts of adenine nucleotides. We discussed the relationship between platelet
dysfunction and adenine nucleotides in platelets of myeloproliferative disorders and
concluded that platelet dysfunction was mainly attributable to reduction of releasable
ADP.
