EFFECT OF DIETARY-FAT ON TOAD LIVER-TUMOR INDUCED BY DMBA - ULTRASTRUCTURAL STUDIES

Toads injected with 2 mg 7,12-dimethylbenza(a)anthracene (DMBA)/toad, 3 times/week for 12 weeks induced liver tumors in 12 out of 50 cases. The electron micrograph of toad liver tumor showed disorganization of the rough endoplasmic reticulum which encircles or partially surrounds the mitochondria. Cristae mitochondrialis are rare in comparison with control. Enhancement of liver tumor incidences (29 out of 50 cases) b y DMBA at the same dose level plus 2cc com oil/toad, 3 times/week for 12 weeks was detected. Electronmicrograph of this group showed the sam e criteria of malignancy as in the first group. No tumor incidences we re detected in toads fed com oil only. The electronmicrograph of liver cells showed a high increase in glycogen and lipid droplets.