Abnormalities of platelet adenine nucleotides in patients with myeloproliferative disorders

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.