二氯化汞对泥鳅红细胞凋亡的影响

用不同浓度的HgCl2饲喂泥鳅20d,观察血红细胞的凋亡情况．结果表明：汞能诱导泥鳅红细胞的凋亡,凋亡率随Hg^＋剂量增大而增加,在第7天凋亡率从7％增至61．2％,光镜下实验浓度为0．8,1．0,1．2mg／L组均观察到红细胞凋亡的典型形态变化．结论：汞能诱导泥鳅红细胞凋亡．     

Enhanced bilirubin binding to different mammalian erythrocytes in the presence of magnesium ions

Effect of magnesium ions on the binding of bilirubin to erythrocytes of different mammalian species, namely, human, buffalo, goat and sheep was studied. Increase in the concentration of magnesium ions led to a gradual increase in the erythrocyte-bound bilirubin in both human and buffalo erythrocytes whereas in sheep and goat erythrocytes, the pronounced increase was found beyond 2.0 and 2.7 mM MgCl₂ concentrations respectively. Percentage increase in erythrocyte-bound bilirubin was found highest in human erythrocytes followed by buffalo and sheep erythrocytes and minimum in goat erythrocytes. These differences in the binding of bilirubin to different mammalian erythrocytes can be attributed to the differential shielding effect of metal ions which involves the masking of negatively charged phosphate of phospholipids found on the erythrocyte surface.     

Studies on the antiperoxide and antihaemolytic action of polyamines using human erythrocytes

Blood RBC's were used to study the role of polyamines, putrescine, spermidine and spermine individually as antioxidants against the peroxidative action of H₂O₂ which leads to haemolysis of erythrocytes. Results indicated that putrescine did not act as antioxidant at all concentrations used in our studies. However, spermidine and spermine suppressed peroxidative changes in RBC's due to the action of H₂O₂ and this suppression was greater with higher concentration of these individual polyamines used, separately. Further, all the three polyamines decreased haemolysis of erythrocytes at all concentrations studied. The action of putrescine to suppress haemolysis of RBC's without showing antioxidant property hypothetically suggests that these properties of respective polyamines may have independent mechanism of action.     

Pre-exercise antioxidant enzyme activities determine the antioxidant enzyme erythrocyte response to exercise

Free radical production increases during exercise and oxidative damage occurs in several tissues. We examined the effects of three different exercise tests on the pattern of change of erythrocyte enzyme antioxidant activities. The tests were a short maximal exercise test, a submaximal prolonged exercise test and a cycling stage during competition. The participants were amateur and professional cyclists with different training statuses and different basal erythrocyte antioxidant enzyme activities. The maximal test produced no changes in the erythrocyte antioxidant enzyme activities of amateur sportsmen. The submaximal test, performed at 80% of maximal oxygen uptake, decreased erythrocyte catalase (12%), glutathione peroxidase determined with H₂O₂ (14%) and glutathione reductase (16%); superoxide dismutase activity increased by about 25%. The cycling stage performed by professional cyclists increased erythrocyte catalase (29%) and glutathione reductase (10%) activities. The in vivo changes in glutathione reductase activity were confirmed by in vitro measurements: hydrogen peroxide decreased and the presence of catalase increased the activity of this enzyme. In conclusion, we suggest that the different erythrocyte antioxidant enzyme responses to diverse exercise tests can be explained by the effects of hydrogen peroxide and the superoxide anion on the antioxidant enzyme activities in erythrocytes.