OBJECTIVETo explore the mechamisms of mitochondria-mediated pathway in apoptosis of platelets resulted from in immune induced bone marrow failure.

METHODSThirty C57BL/6 mice were randomly divided into 3 groups (10 mice in each group): normal group, model group, cyclosporine A(CsA) group. Mouse model of immune bone marrow failure were established. After mouse model was successfully established, the mice in normal group and model group were given saline orally, the mice in CsA group was treated with CsA orally. Blood routine examination of mice in each group was performed by automatic blood cell analyzer; the mitochondrial membrane potential(ΔΨm), cytochrome C(Cyt C), phosphatidylserine (PS), Cawere measured by flow cytometry; expression of BAX, BAK, caspase-3, caspase-8, caspase-9 was detected by using Western blot method, the changes of bone marrow platelet ultrastructure were observed under transmission electron microscope.

RESULTSCompared with normal group, the platelet count of model group decreased significantly, while the level of ΔΨm, caspase-3, caspase-8, caspase-9 significantly decreased, the level of Cyt C, PS, Ca, BAX, BAK increased significantly (P<0.05). Compared with the model group, the platelet count of CsA group increased obviously, while the level of ΔΨm, caspase-3, caspase-8, caspase-9 of CsA group increased significantly, the level of Cyt C, PS, Ca, BAX, BAK of CsA group decreased significantly (P<0.05). Electron microscopy showed that compared with the model group, platelet damage in CsA group were alleviated.

CONCLUSIONmitochondrial pathway plays an important role in the reduction of platelet resulted from immune bone marrow failure.