Effect of prolonged administration of gastrin on experimental carcinogenesis in rat colon induced by intrarectal instillation of N-methyl-N'-nitro-N-nitrosoguanidine.

Helicobacter pylori infection enhances glandular stomach carcinogenesis in Mongolian gerbils treated with chemical carcinogens.

Helicobacter pylori (Hp) is thought to be a stomach carcinogen from epidemiological findings. To determine the effects of infection with the bacteria on experimental carcinogenesis, a study of the glandular stomach of Mongolian gerbils (MGs) was performed. Male MGs were treated with N-methyl-N'-nitro-N-nitrosoguanidine followed by inoculation with Hp or infected with Hp followed by N-methyl-N'-...

Germ-free and Conventional F344 Rats Promoting Effect of Bile Acids in Colon Carcinogenesis in

SUMMARY The promoting effect of sodium cholate or sodium cheno-deoxycholate on colon carcinogenesis was studied in fe male F344 germ-free and conventional rats. Both germ-free and conventional rats received intrarectal instillations of N-methyl-A/'-nitro-/V-nitrosoguanid¡ne (MNNG) for 2 weeks (total dose, 8 mg/rat) and then intrarectal doses of sodium cholate or sodium chenodeoxycholate (20 mg...

Effect of calcium on rat gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine.

The effect of calcium carbonate (CaCO3) on the initiation of gastroduodenal carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was examined under the conditions with and without sodium chloride. Male Wistar rats were given drinking water containing MNNG (100 mg/liter) and one of the following diets during the first 20 weeks ad libitum. Group 1 was given basal diet; group 2, d...

Naringenin Inhibits Oxidative Stress Induced Macromolecular Damage in N-methyl N-nitro N-nitrosoguanidine Induced Gastric Carcinogenesis in Wistar Rats

Dose-dependent DNA ruptures induced by the procarcinogen dimethylnitrosamine on primary rat liver cultures.

The effect of certain procarcinogens, among which demethylnitrosamine (DMN) is included, has been difficult to detect in several short-term assays. An alternative system, in which DMN effects could be easily quantitated, might be useful in studies of chemical carcinogenesis and environmental contamination. To develop such a system, we tested the possibility of measuring the amount of breakage p...