Large intestinal carcinogenesis. I. Promotional effect of dietary fatty acid isomers in the rat model.
For evaluation of the promotional effects of dietary trans-fatty acids on large intestinal carcinogenesis, 120 inbred female F344 rats were divided into 6 groups and fed a 25% elaidic acid diet, a 25% oleic acid diet, or a regular (4.5% fat) chow diet. Ninety animals, 30 per dietary group, received weekly im injections of azoxymethane (2 mg/kg; CAS: 25843-45-2). None of the 30 saline-injected control animals, 10 per dietary group, fed any of the three diets developed tumors. There were twice as many animals with adenocarcinoma of the large intestine from the trans-fatty acid diet group as compared with either the cis-fatty acid diet group or regular diet groups. Chi-square analysis showed that the difference between the incidence of large intestinal carcinomas was not significant between the cis- and trans-fatty acid diets. The difference between the regular diet and trans-fatty acid diet groups was not significant at the 5% level (P = .08). A higher, but nonstatistically significant, incidence of nephroblastomas and squamous ear duct neoplasms was also observed in carcinogen-treated animals maintained on each of the high-fat diets as compared with the incidence of both in treated animals fed the regular chow diet.
D000818:Animals; D001397:Azoxymethane; D004041:Dietary Fats / Q000494:pharmacology*; D004357:Drug Synergism; D005227:Fatty Acids / Q000494:pharmacology*; D005260:Female; D007414:Intestinal Neoplasms / Q000139:chemically induced* / Q000473:pathology; D007536:Isomerism; D019301:Oleic Acid; D009829:Oleic Acids / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013329:Structure-Activity Relationship
D004041:Dietary Fats; D005227:Fatty Acids; D009829:Oleic Acids; D019301:Oleic Acid; C011459:elaidic acid; D001397:Azoxymethane