ESOPHAGEAL CARCINOMA AND EPITHELIAL DYSPLASIA IN BEAGLE DOGS INDUCED BY N-ETHYL-N'-NITRO-N-NITROSOGUANIDINE

Abstract

Fourteen male 6 months old beagle dogs were given solution of N-ethyl-N'-nitro-N-nitro-soguanidine at a concentration of 150μg/ml or 100μg/ml for 5 to 9 months.
Eight out of 14 dogs developed esophageal squamous cell carcinoma, and four developed epithelial dyslasia of the esophagus without squamous cell carcinoma. Good correlation was found between the conditions of administration of ENNG and the induced esophageal lesions. For the induction of squamous cell carcinoma, administration in the condition of 150μg/ml for 6 months or 100μg/ml for 9 months was suitable. For the selective induction of early esophageal carcinoma, the condition of 100μg/ml for 8 months was suitable.
For the induction of epithelial dysplasia without carcinoma, 100μg/ml was suitable. It was clarified that by the selection of the concentration and the period of administration of ENNG, it is possible to induce esophageal squamous cell carcinoma or epithelial dysplasia selectively.