CHANGE OF NA(-ATPASE ACTIVITY DURI NG REPRODUCTION OF TICK-BORNE ENCEPHALITIS-VIRUS IN SPEV CULTURE(),K(+))

Changes in the activity of Na(+),K(+)-ATPase during infection of SPEV cells with tick-borne encephalitis (TBE) virus were studied in prepara tions of cell membranes and directly in the culture and the effect of this enzyme activity on the penetration of TBE virus in the cells and production of virus-specific proteins investigated, The highest activi ty of the enzyme was observed directly after challenge and during the 5th and 6th hours of infection, whereas the lowest was recorded during the second and third hours and 24 h postinfection. A similar decrease in the activity of this ATPase was observed in the brain cells of inf ected mice. Oubaine and low (0 degrees C) temperature prevented the vi rus penetration in the cells, which indicates that this process is ene rgy-dependent. Inhibition of Na(+),K(+)ATPase led to a drop in thc pro duction of virus-specific protein.