Calcium metabolism of the thrombocytes in ischemic heart disease

Changes in Ca++ concentration were studied in platelets of patients with acute myocardial infarction, unstable or stable angina pectoris and those of healthy donors by means of fluorescent probe Quin-2 AM. Influence of aggregation inductors on the process of Ca++ level increase in these cells was also investigated. Intracellular Ca++ concentration increased in patients with acute myocardial infarction in the presence of PAF 2.10(-7) M (1337 +/- 255 nM) and in the presence of ADP 10(-5) M (1767 +/- 296 nM). A certain increase in calcium responses to stimulators was observed also in patients with unstable or stable angina pectoris. Dynamic follow up of patients with acute myocardial infarction starting from the 14th day demonstrated significant fall in intracellular Ca++ concentration (from 1767 +/- 296 nM to 834 +/- 186 nM, p less than 0.01). Platelet sensitivity to inductors during the course of therapy did not change significantly in patients with stable angina pectoris and tended to decrease in those with unstable angina pectoris (from 707 +/- 274 nM to 410 +/- 95 nM, p greater than 0.05). Increase in platelet aggregability and in calcium responses to stimulators in patients with IHD is an evidence of calcium metabolism disturbances which play an important role in the pathogenesis of the disease.