动物造模,自发性肿瘤动物模型 z-bio 2023-10-31 1181

　　Rats have a large body size and provide a large amount of tissue, making it convenient for experimental operations such as surgery and injection. The application of rat spontaneous tumors in tumor research is second only to mice, and its incidence is not only related to strain, but also to nutrition and infectious diseases. The widely used LEC (long evans cinnamon) liver cancer naturally occurring rat model was initially established by Joseph A. long and Herbert M Evans of the University of California in the United States. About 40% of LEC rats suddenly develop acute hepatitis with symptoms such as jaundice, bleeding, and oliguria around 4 months after birth, and may die within about 1 week; About 60% of rats experience chronic hepatitis, with significantly increased serum alanine aminotransferase and oxalate aminotransferase activities. The liver exhibits placental glutathione peroxidase (GST-P) positive proliferative nodules, which save one year from developing liver cancer. The characteristics of this model are very similar to those of Wilson's disease in humans. Overall, compared to mice, the incidence of spontaneous tumors in rats is lower, and histologically, sarcomas are more common than cancers. Except for liver cancer, breast fibroadenoma, and testicular tumors in F344 rats, the incidence of tumors in the digestive system, central nervous system, and respiratory system of rats under 18 months old is very low. Therefore, in a specific group and strain of rats, their age is crucial for determining their tumor incidence.

　　1. Breast tumors in rats are the most common site of tumors in most groups and strains of elderly female rats, with a high incidence rate of up to 30% to 60%. These tumors can also occur in male rats, but the incidence is much lower. Benign fibroadenoma is the most common type, and adenocarcinoma fibroadenoma can also occur. According to reports, the incidence of spontaneous breast tumors in female SD rats is about 55%; The incidence of spontaneous malignant breast tumors in WN female mice ranges from 30% to 50%; The incidence of breast cancer in F344 female mice was 41%, and the incidence of breast fibroadenoma was 9%; The incidence of breast cancer in OM female mice was 26%~30%; The incidence of breast fibroadenoma in WAG female mice is 21%, with a higher incidence of WAG/Rij; The incidence of breast cancer in WF female mice was 21%; The incidence of white haired breast tumors in ACI female mice is 11%; The incidence of fibroadenoma in the breast of BN female mice is 11%.

　　2. The most common pituitary tumor in rats is a refractory adenoma, and the incidence of pituitary tumors in female rats of the same strain is much higher than that in male rats. The survey shows that the incidence of pituitary adenoma in F344 strain is 36% in female mice and 24% in male mice; The incidence of pituitary adenoma in BN series is 26% in female mice and 14% in male mice; 21% of female and 5% of male mice with ACI spontaneous pituitary adenoma; The incidence of pituitary tumors in WF female mice is 27%; 20% to 40% of animals aged over 18 months in the M520 series have anterior pituitary adenoma; The incidence rate of pituitary tumors in WN series>18 months old was 40%~93%. In addition, the incidence rate of pituitary adenoma in rats is in Osbo