ABSTRACT
Objective To study the influencing factors and quality control of chromosome preparation during chromosome aberration test in vitro,and to summarize and analyze the method and key points of successful preparation of chromosome specimens in vitro. Methods Chinese hamster lung cells(CHL)were used for cell culture and chromosome preparation. Mitomycin and cyclophosphamide were used as positive mutagens. After routine hypotonic treatment,fixation, and squash preparation, finally, to read the film under the microscope. Results The CHL chromosome aberration test showed that both the chromosome aberration rates of mitomycin- and cyclophosphamide-treated cells were significantly increased(>20%),while the aberration rates in the negative control group were less than 5%, either with and without metabolic activation. The success rate was high and the prepared chromosomes were well dispersed with a moderate length. Conclusions Many factors can affect the specimen preparation in chromosome aberration test. Every step is very important,and it should be strictly following the operating procedures. It is of importance to grasp the principle of each step and to operate carefully,patiently and scientifically in order to prepare good specimens.
ABSTRACT
Objective To evaluate the mutagenicity of hydrolysate of Meretrix meretrix Linnaeus soft tissue, so as to provide experimental basis for its exploitation.Methods Three mutagenicity tests were used to evaluate the mutagenic effects, including Ames test, CHL chromosome aberration assay and bone marrow micronucleus assay in mice.Results In Ames test, the revertant colonies numbers in each group were twice less than the numbers of spontaneous revertant colo-nies, five bacterial strains showed negative results with or without S9 activation, and the result of Ames test was negative. The CHL chromosome aberration assay and bone marrow micronucleus assay showed that the chromosome aberration rate and micronucleus rate of each dose group showed no significant difference compared with the negative control group, respec-tively ( P>0.05) .Conclusions Under this condition, the results show that all of the Ames test, chromosome aberration assay and bone marrow micronucleus assay are negative, and no mutagenicity is observed in the hydrolysate of Meretrix mer-etrix Linnaeus soft tissue.