Nude mouse in studies on chemical carcinogenesis

Area of Science:

• Biochemistry
• Toxicology
• Immunology

Background:

• The skin of nude mice contains monooxygenase enzymes, crucial for metabolizing xenobiotics.
• These enzymes play a role in the bioactivation of chemical carcinogens.
• Nude mice have a unique immune deficiency, affecting their response to foreign substances.

Purpose of the Study:

• To investigate the activity of monooxygenase enzymes in nude mouse skin.
• To assess the sensitivity of nude mouse fibroblasts to chemical carcinogens.
• To evaluate the potential of the nude mouse model in chemical carcinogenesis research.

Main Methods:

• Assessing monooxygenase enzyme activity in nude mouse skin.
• Administering 3-methylcholantrene intraperitoneally to induce enzyme activity.
• Culturing nude mouse fibroblasts for transformation assays with carcinogenic chemicals.
• Comparing transplant acceptance of transformed cells in nude mice versus conventional animals.

Main Results:

• Monooxygenase enzyme activity in nude mouse skin significantly increased after 3-methylcholantrene administration.
• No significant change was observed in UDP-glucuronosyltransferase activity, indicating specific induction of the monooxygenase system.
• Nude mouse fibroblast cultures demonstrated sensitivity to transformation by carcinogenic chemicals.
• Nude mice exhibited enhanced acceptance of transplanted transformed cells compared to conventional laboratory animals.

Conclusions:

• The nude mouse model exhibits inducible monooxygenase activity in the skin, relevant for carcinogen metabolism studies.
• Nude mouse fibroblasts are susceptible to chemical-induced transformation, supporting their use in genotoxicity testing.
• The enhanced ability of nude mice to accept transplants of transformed cells makes this model valuable for in vivo transformation assays.