[Activity of nucleolar organizers in megakaryocytes from patients with leukemia].

The activity of nucleolar organizer regions (NOR) in megakaryocytes (MK) from 21 patients with acute lymphoblastic leukemia (ALL), 35 patients with acute nonlymphoblastic leukemia (ANLL) and 12 patients with blast crisis of chronic myeloid leukemia (BC CML) were studied by silver staining. The control group consisted of 12 donors. The activity of NOR in the whole population of MK and in groups of MK with 1-3, 4-6, 7 and over lobules per nucleus (MK 1, 2 and 3 class, respectively) were taken into account. The activity of NOR in the group of first class MK from patients with acute leukemia (ALL and ANLL) was detected low. On the contrary, it was high in the group of third-class MK of those patients, as compared to the control. The activity of NOR in MK of BC CML patients was significantly lower as compared both to the control and to patients with acute leukemia. The cause of changing the functional state of MK in varying hematology disease has been discussed.