IS AN INCREASE OF DEOXYRIBONUCLEASES ACTIVITY IN UREMIC LYMPHOCYTES CAUSED BY THEIR AUGMENTED SYNTHESIS IN THESE CELLS

Deoxyribonucleases activity in T and B lymphocytes isolated from 45 pa tients with chronic renal failure and 30 control subjects was measured . The results obtained clearly show a dramatic increase in enzyme acti vity in both T and B lymphocyte cells isolated from uraemic patients w hen compared with the control cell. The increase in enzyme activity wa s limited to the group of relatively small nucleases ranging from 14 k Da to 18 kDa. Since it was shown previously that these nucleases are a mong the cleavage products of the largest subunit of DNA-dependent RNA polymerase class I, it is suggested that a characteristic feature of the lymphocyte cell isolated from uraemic patients is increase of RNA polymerase lability, thus resulting in RNA synthesis decrease. Amongst toxins increasing catabolism of the active polymerase enzyme, a signi ficant correlation with the vise of lymphocyte Mg2+ and Mn2+ ions was disclosed.