铁皮石斛对小鼠致突变作用的检测研究

Study on the mutagenic action of dendrobium candidum on mice

目的采用小鼠骨髓细胞微核试验和精子畸形试验研究铁皮石斛对小鼠的致突变作用。方法将50只昆明种小鼠随机分为5组。以不同剂量(5000 mg/kg、2500 mg/kg、1250 mg/kg)的铁皮石斛分2次经口灌胃染毒小鼠,每次间隔24 h,于末次染毒后6 h颈椎脱臼法处死小鼠,取股骨骨髓常规制片,Giemsa染色,在油镜下检测骨髓嗜多染红细胞微核率;另将25只雄性昆明种小鼠按上述剂量和分组经口灌胃连续染毒小鼠5 d,于首次染毒后第35 d用颈椎脱臼法将小鼠处死,取其双侧附睾制成精子悬液后制片,伊红染色,在高倍镜下观察精子畸形率。两项实验同时设阴性对照组(纯水)和阳性对照组(环磷酰胺40 mg/kg)。结果铁皮石斛各剂量组均未见致小鼠骨髓嗜多染红细胞微核和精子畸形作用。结论在本实验条件下,铁皮石斛对小鼠无致突变作用。

Objective Mouse bone marrow micronucleus test and mouse sperm abnormality test were used to study the mutagenic action of dendrobium candidum on mice. Methods Fifty mice of kunming species were randomly divided into 5 groups. Then the mice were orally given dendrobium candidum at different doses（5000 mg / kg,2500 mg / kg,1250 mg / kg） twice with interval of 24 h. The mice were killed by cervical dislocation after 6 h of the last exposure,then the femoral bone marrow was taken for conventional production and Giemsa staining to observe the micronucleus frequency（MNF） of polychromatic erythrocytes（PCE） under the oil mirror. In addition,another 25 male mice of kunming species were also divided into 5 groups and orally given dendrobium candidum at the above doses once a day for 5 consecutive days. Then the mice were killed by cervical dislocation after 35 days of the initial exposure,then the bilateral epididymis were taken to produce sperm suspension for conventional production and eosin staining,and the sperm deformity rate was observed under the high power lens. The negative control group（pure water） and positive control group（cyclophosphamide 40 mg / kg） were both set in the two experiments at the same time. Results Abnormality of mouse bone marrow polychromatic erythrocytes micronucleus and sperm were not found in each dosage group of dendrobium candidum. Conclusion Under the present experimental conditions,dendrobium candidum showed no mutagenic effect on mice.