Features of cell cycle and lung cell DNA fragmentation in rats within 1, 3 and 7 days after skin burns
The topic presents the results of the study of lung cell cycle kinetics parameters in rats, determined by method of flow DNA-cytometry with underlying thermal burn injuries to the skin and administration of 0,9 % NaCl solution on 1 <sup>-st</sup>, 3 <sup>-nd</sup> and 7 <sup>-th</sup> days after injury. It was found that the parameters of lung cell cycle in rats with no significant burn injuries were characterized by a predominance of G0G1 cells and the balance between the processes of synthesis (S-phase) and apoptosis (SUB-G0G1 interval). The apoptosis (increase in number of cells within SUB-G0G1 interval) while maintaining the ability of cells to DNA synthesis (S-phase) dominated within a day after burn injuries. At the same time, a number of G0G1 cells also increased, along with an increase of proliferative unit and decrease of proliferation index, on account of reduction in number of G2 + M cells. We noticed a decrease in G0G1 cell population and increase of proliferation index under further development of burn injury within 3 days after registration of burns. A significant number of cells with fragmented DNA and increased parameters of proliferation unit remained on 3 and 7 day of the experiment. Also, we observed an increased S-phase index in animals with burn injuries 3 and 7 days after actual burns compared with the same index in animals with no burns.