取样时间对小鼠骨髓和外周血嗜多染红细胞微核率的影响

EFFECT OF SAMPLING TIME ON MOUSE MICRONUCLEUS ASSAY IN BONE MARROW AND PERIPHERAL BLOOD

目的 :比较一次给药后不同采样时间对鼠外周血和骨髓嗜多染红细胞微核率的影响。方法 :ICR小鼠一次腹腔注射 (IP)MMC 2 0mg/kg .bw或CP 40mg/kg .bw ,后 12h、18h、2 4h、32h、48h、72h采外周血及骨髓涂片 ,Giemsa染色 ,计数嗜多染红细胞及其微核数。结果 :一次IPMMC或CP后 12h即可观察到小鼠骨髓PCE微核率增高 ,分别在给药后 2 4h、32h达到高峰 ,此后逐渐下降 ,到 72h已接近对照组水平 ;而外周血PCE微核率的显著增高则出现在给药后的 2 4h ,在 48h达到高峰。结论 :外周血PCE作为微核试验靶细胞与骨髓PCE的检测敏感性相同 ,但外周血PCE微核高峰出现较骨髓延迟约 12～ 2 4h ;在检测化学物对骨髓细胞毒性方面 ,外周血与骨髓的检测灵敏性也相同。

Purpose: Studies were conducted to evaluated the effects of one treatment protocol and sampling time on the micronucleus tests of two clastogens-mitomytin C and cyclophosphamide. Methods: Young adult ICR mice were treated once with mitomytin C (MMC, 2 mg/kg.bw) or cyclophosphamide (CP, 40 mg/kg.bw) by intraperitoneal injection. The micronucleus incidences in polychromatic erythrocytes (PCEs) of different sampling times-12 h, 18 h, 24 h,32 h, 48 h, 72 h after dose were evaluated in the peripheral blood and the bine marrow. Results: The date in this study indicated: ① The frequencies of micronucleatde polychromatic erythrocytes (MnPCEs) in the bone marrow and peripheral blood were almost identical at each optimal sampling time of the two clastogens; ② The maximal increase of the incidence of MnPCEs of peripheral blood was delayed 12～24 h compared to that of bone marrow; ③ The frequency of PCEs of peripheral blood was equal sensitive to that of bone marrow in detecting cytotoxicity to the hematopoitic system. Conclusion: It is suggested that following the one injection protocol with MMC or CP, bone marrow and peripheral blood are both equaly efficacy.