Changes in the number of haemopoietic stem cells (CFUs) in bone marrow and spleens of pregnant rats after a short space flight onboard the Cosmos-1514 biosatellite.

After a 5-day stay in a state of weightlessness onboard a biosatellite Cosmos-1514 the pregnant rats exhibited a decrease in the number of haemopoietic stem cells (CFUs) in bone marrow and spleens on the recovery day after the space flight as compared to rats kept in the vivarium under usual conditions. The different changes in the concentration of CFUs in the bone marrow and spleens of flight and synchronous control rats indicate that the extent of the decrease in CFUs pool in the spleens of flight rats was significantly influenced by the action of non-specific flight factors.