超氧自由基（O^—2）对环磷酰胺所致小鼠骨髓细胞损伤效应的影响

目的：探讨高浓度超氧自由基（O^-2)在环磷酰胺（CTX）致小鼠骨髓细胞抑制中的作用及自由基清除剂超氧化物歧体酶（SOD）的保护作用。方法：40只小鼠随机分为4组，分别腹腔注射生理盐水（对照组）、低（37．5mg/kg）、中（56．25mg/kg）及高（75mg/kg)剂量CTX；另用20只注射了剂量CTX的小鼠再分别腹腔注射SOD和生理盐水。结果：不同剂量CTX腹腔注射后，小鼠骨髓细胞中O^-2含量明显高于正常对照组（P＜0．01），在而骨髓细胞计数和^3H-TDR掺入法测定的DPM（每分钟衰变计数）值则明显低于正常对照组（P＜0．01）；经SOD保护后，骨髓细胞计数，O^-2含量及DPM值均与正常对照组无统计学意义（P＜0．01）。结论：CTX所致的高浓度O^-2是造成骨髓细胞损伤的重要机制之一，SOD对CTX所致的损伤效应有保护作用。

The role of superoxide (O-2) in the damage of bone marrow cells induced by cyclophosphamide in mice

Objective To investigate the noxious effect of superoxide (O- 2) and the protective action of superoxide dismutase (SOD) on the depression of the proliferation of bone marrow cells induced by cyclophosphamide (CTX) in mice. Methods 40 rats were divided randomly into 4 groups.They were administered intraperitoneally normal saline (control) and CTX of low (37.5 mg/kg),middle (56.25 mg/kg) and high (75 mg/kg) doses respectively. Another 20 rats, divided into 2 groups (10 for each) were first given intraperitoneally a high dose of CTX and then normal saline and SOD solution respectively. Results The content of O- 2 in bone marrow cells was evidently and proportionally higher in the CTX groups than that in the control group (P<0.01). The bone marrow cell count and DPM were significantly decreased in the CTX groups (P<0.01). The values of bone marrow cell count, DPM and O- 2 content in the CTX group with SOD added differed markedly from that without (P<0.01), but approximated those in the group of normal mice (P>0.05). Conclusion High concentration of O- 2 induced by CTX may be one of its mechanisms affecting the proliferation of bone marrow cells, and SOD protects the bone marrow cells from the toxicity of CTX in mice.