An ultrastructural and ultracytochemical study of peripheral blood thrombocytes in women with habitual spontaneous abortion
: An ultrastructural and ultracytochemical analysis of platelets was performed to assess the activity of 5'-AMPase and ATPase using a leukoconcentrate of the peripheral blood cells of non-pregnant women suffering from recurrent spontaneous abortion. The blood platelet populations were found to have increased proportions of light thrombocytes in phases I and II of the menstrual cycle, which was associated with pronounced ultrastructural and cytochemical signs of a release reaction showing their activated state: reduced density of the hyaloplasm, diminished quantity of specific and glycogen granules, development of the vacuolar system, 5'-AMPase and ATPase activity on the plasmalemma, light hyaloplasm, and in released specific granules and vacuoles. The release reaction is associated with a high contact activity of platelets which results in the formation of small and large platelet aggregates and attachment of other blood cells--erythrocytes, lymphocytes, and granulocytes. The intercellular fluid contains membrane fragments of destructive cells, including platelets with 5'-AMPase and ATPase activities, which may result in thromboplastin formation.