The Genotoxical Test Of Carbon Disulfide On Male Mice By Sub-Chronic Inhalation

Carbon Disulfide (CS2), a well-known volatile solvent, is widely used in the manufacture of viscose rayon, cellophane, carbon tetrachloride, rubber chemicals and pesticides. It is also used in laboratory. For a long time, the study of affection of industrial poison and environments compound to neural system and cardiovascular system of human were received great regards, but put less importance to reproductive system particularly male reproductive systemHowever, there are few literatures reporting the genetic toxicity of CS2 around the world. External researches almost reported that carbon disulfide has no genetic toxicity. Although internal researches reported that CS₂ will induce DNA damage, increase in the frequencies of aneuploidy and micronucleus. But the methods and the concentration of CS₂ in these researches are different. The mechanism of genetic toxicity of CS₂ is still far from clear. Thus, there is an urgent need for the development of screening assays for genetic toxicity.The experiments which stimulated the ways the workers touched poison, used main organ weight coefficient, spermatic malformation, pathologic tissue slice up, flow cytometry and single cell gel electrophoresis (SCGE) to analyze the damages to germ cell of mice.Objective:To general evaluate genotoxicity of germ cell of mice using weight coefficient, spermatic malformation assay, pathologic tissue slice up of testicle, flow cytometry and single cell gel electrophoresis (SCGE) by Sub-Chronic inhalation carbon disulfide; and it could provide as laboratorial basis in order to further research its damage mechanism to reproductive system.Methods:The animal model was made by Sub-Chronic static inhalation carbon disulfide. All the mice were divided into four groups, i.e. normal control, low, middle and high dosage. Theweight coefficient was detected by using main organ weight coefficient; sperm abnormality was detected by spermatic malformation assay; pathologic changes of testicle was used to detected morphological changes of testicle; the apoptosis rate of germ cell was detected by flow cytometry and detection of carbon disulfide induced DNA single strand breakage in mice's sperm using single cell gel electrophoresis (SCGE),and perfected the SCGE in sperm. Results:1. The weight coefficient was descending along with the increase doses of exposed carbon disulfide, the middle and high groups compared with normal control group, the difference is significant (P<0.05).2. The sperm count was decreased but the rate of sperm abnormality was increased along with the increase dose of exposed carbon disulfide, the middle and high groups compared with normal control group, the difference is significant (P<0.05).3. For the changes of testicle, in low group, the primary spermatocyte fission is abnormality, chromatin turns light and arranged sparseness, the count of sperm has little decrease, sometime nuclear fission can be seen. The volume of androgonial cell and primary spermatocyte diminished and the count obviously decreased, and the mature germ cell can be hardly found in middle and high groups. Contrarily, the Spermatogenic epithelium of normal control has a large number of cells, furthermore, the androgonial cell and primary spermatocyte arranged orderly, and the shape of cell is normal.4. The apoptosis of germ cell of mice appeared clearly, along with the increase doses of exposed carbon disulfide. Obviously, the apoptosis appeared from middle dose group, but there is not significant difference among low, middle and normal control groups except high groups (PO.05).5. The degree of DNA damage, the rate of sperm with comet-like tail and the tail length were increased significantly (PO.05), r=0.68, along with the increase doses of exposed carbon disulfide. A significant decrease was clearly observed inpercentage of head in all dose groups compared to that of the control group (P<0.05), there is a good dose-response relationship in all dose groups and control, r=-0.827. Concludes:The Sub-Chronic Inhalation of carbon disulfide can not only result in increase the rate of sperm abnormality, the weight coefficient of testis and the mature sperm in testis were decreased, but also induce the apoptosis and DNA damage of germ cell. The modified and approved technique of single cell gel electrophoresis (SCGE) is simple, fast, and high sensitive, and it can be used to detect DNA damage to germ cell of male mice.