关键词: Wistar 大鼠, 脏器质量及系数, 肿瘤, 死亡原因

Abstract: Abstract: Objective To observe the weight of viscera and organ coefficient，and occurrence of spontaneous tumor of survival and dead Wistar rats during 2 years experiment，and investigate their death cause． Method The gross anatomy and histopathological examination for the rats sacrificed at the end of the two-year experiment and the dying or dead rats during the experiment were carried out instantly． Their body weight and weight of their brain，heart， lung，liver，spleen，kidney，adrenal glands，thymus，ovary，uterus，testis，and epididymis were measured and organ coefficients were calculated，and occurrence of spontaneous tumor was recorded． Result There were significant differences in weight of body，brain，heart，lung，liver，spleen，kidney，adrenal glands and organ coefficients of brain and adrenal glands between female and male rats survived for 104 weeks． The gross anatomy and histopathological examination revealed that 80. 5% of rats died of dyscrasia and multiple organ failure ( MOF) resulted from tumor lesions，17. 1% of rats died of MOF resulted from non-tumor lesions，and 2. 4% of rats succumbed to MOF caused by other lesions． There was no significant difference in death cause between male and female rats． Conclusion The present study provided background information for carcinogenicity tests performed on Wistar rats，and the tumor lesions are the leading death cause of Wistar rats．

Key words: Wistar rats, organ weight and coefficient, tumor, death cause