[Rna content of gerbil hepatocytes after the flight aboard space platform Foton-M3]

The paper compares and contrasts the results of measuring the hepatocyte cytoplasm area and RNA content in 35 gerbils in three series of experiments, i.e. the vivarium control, modeled space flight (synchronous control) and exposure to the factors of 12-d Foton-M3 orbital flight. Central, intermediate and peripheral zones of hepatic lobes were subjected to histological and histochemical analyses to measure the hepatocyte cytoplasm area; the RNA content was determined from the level of cytoplasm basophilia after azure staining. Cytometric and cytophotometric investigations were performed using image analyzer Video-7-Test-Morpho. In the vivarium animals, hepatocytes with the largest cytoplasm localized predominantly in the intermediate and central zones of the lobes. Judging from the results of microdensitometry, the RNA content was particularly high in binucleate hepatocytes of the intermediate zone. In the synchronous control, hepatocytes tended to grow in size, in the peripheral zone specifically, whereas RNA content was largely equal no matter hepatocyte topography. After space flight, cytoplasm enlargement transcended this process in the vivarium animals. The cytoplasm RNA content along the entire liver parenchyma made a significant decrease equally as compared with the vivarium and synchronous control animals.