Related Experiment Video
Updated: Jul 28, 2026
07:01
An Orthotopic Mouse Model of Anaplastic Thyroid Carcinoma
Published on: April 17, 2013
Thyroid tumors in rats from tetramethylthiourea
Journal of Environmental Pathology and Toxicology
|January 1, 1979
Summary
Tetramethylthiourea (TMTU) exposure in rats led to thyroid changes and cancer in females. High doses of TMTU caused adverse effects, including thyroid follicular cell carcinomas in female rats.
Area of Science:
- Toxicology
- Carcinogenesis
- Endocrinology
Background:
- Tetramethylthiourea (TMTU) is a chemical compound with potential toxicological effects.
- Understanding the long-term impact of TMTU on mammalian health is crucial for risk assessment.
Purpose of the Study:
- To evaluate the chronic toxicity and carcinogenicity of Tetramethylthiourea (TMTU) in rats.
- To determine dose-response relationships and identify target organs for TMTU toxicity.
Main Methods:
- Rats (male and female ChR-CD) were fed diets containing 0, 30, or 300 ppm TMTU for up to 2 years.
- Body weight, diet consumption, hematology, urinalysis, and serum thyroxine levels were monitored.
- Gross and histopathological examinations of tissues, particularly the thyroid, were performed.
Main Results:
- High-level TMTU exposure resulted in reduced body weight and diet consumption in rats.
- Anemia, polyuria with low osmolality, and decreased serum thyroxine were observed in high-level exposure groups.
- Thyroid follicular cell hypertrophy, hyperplasia, and enlargement were noted in high-level TMTU-fed rats.
- Female rats exposed to high-level TMTU developed follicular cell carcinomas (28%), a statistically significant finding compared to controls.
Conclusions:
- Tetramethylthiourea (TMTU) induces significant thyroid gland alterations in rats.
- TMTU is carcinogenic in female rats, causing follicular cell carcinomas.
- Long-term exposure to TMTU poses a carcinogenic risk, particularly to the female rat thyroid.
