Abstract
The effects of hydroxypyruvaldehyde phenylosazone (1) and its CH3-and Cl-derivatives (2-5) on the osmotic fragility of bovine erythrocytes treated or untreated with sphingomyelinase C of Bacillus cereus were examined by coil planet centrifugation (CPC). These drugs proved to stabilize sphingomyelinase C-untreated erythrocytes as well as erythrocytes which had been treated with the enzyme in the presence of Ca2+ and / or Mg2+ : The peak of hemolysis normally observed in the untreated erythrocytes in the range between 50 and 100mOSM shifted to the range of 40 to 90 mOSM when CPC was performed in the presence of the drugs 1-5, indicating an increase in the osmotic stability of these cells. The bands between 135 and 160 mOSM and between 160 and 200 mOSM which were produced by treatment of the erythrocytes with sphingomyelinase C in the presence of 10mM Ca2+ and / or 10mM Mg2+ disappeared when CPC was carried out in the presence of the drugs. In this case, the peak of the hemolytic band between 50 and 100 mOSM also shifted to the range of lower osmolarity, i.e. between 30 and 80 mOSM or between 40 and 90 mOSM, indicating stabilization of sphingomyelinase C-treated bovine erythrocytes. Observations by scanning electron microscopy showed that the drug-induced deformability of bovine erythrocytes was altered or almost completely destroyed by treatment with sphingomyelinase C of Bacillus cereus.
