动物造模 z-bio 2022-04-28 371

　　Objective To carry out in vivo chromosomal aberration experiments in ICR mice, by administering cyclophosphamide and colchicine at different time points, to compare the effects of different administration/collection time points and different administration concentrations on the incidence of chromosomal aberrations in mouse bone marrow cells.

　　Methods A total of 36 ICR male mice of about 7-8 weeks old were randomly divided into the sampling group at 18 h after drug administration and the sampling group at 24 h after drug administration. kg (2h before sampling, ip) administration group, with 0.9% sodium chloride injection as vehicle control, CP 0mg/kg, 10mg/kg and 40mg/kg were administered respectively, 3 animals in each group. The body weight of animals before and after administration was recorded during the experiment. The negative control group and the 10 mg/kg CP group were administered twice at an interval of 24 hours, and the 40 mg/kg CP was administered in a single dose. The samples were collected 18h or 24h after administration, and COL was injected intraperitoneally 2h or 4h before the sample. The bilateral femurs of all experimental animals were harvested, and the bone marrow cell suspension was collected to prepare Ciemsa chromosome specimens for analysis of chromosomal aberration types, and the average structural aberration cell rate (excluding ctg and csg, AC%) and structural aberration cells in each group were calculated. rate (including eg and esg, ACG%), multi-aberrant cell rate (excluding ctg and esg, MAC%) and polyploid cell rate (PC%).

　　Results The CP and COL used in this study had no significant effect on the body weight of the animals, and the dosage and frequency of administration were feasible. Compared with the vehicle control group in each group, the AC%, ACG% and MAC% of all CP administration groups were significantly increased (P<0.01), and the chromosomal damage was more serious at high doses; CP18h- The AC%, ACG% and MAC% of the COL4h group were lower than those of the CP18h-COL2h group, and there was a significant difference (P<0.05)), suggesting that the use of a high dose of COL (10 mg/kg) could produce additional chromosomal damage. Most of the structural aberrations in the vehicle control group were clefts, while chromosome monosomy and chromosome breakage were the most important types of aberrations caused by CP.

　　Conclusion When carrying out the chromosome aberration test of ICR mice, it is ideal to take samples about 18 hours after CP administration and 4 hours after COL administration. Through the exploration of experimental conditions, this study not only accumulated background data, but also provided reference for relevant researchers.