Effects in Rats of Sodium Chloride on Experimental Gastric Cancers Induced by N-Methyl-N′-nitro-N-nitrosoguanidine or 4-Nitroquinoline-1-oxide2

Abstract

The effects were studied of NaCl on the production of gastric carcinomas by N-methyl-N-nitro-N-nitrosoguanidine (MNNG) and by 4-nitroquinoline-1-oxide (NQO) in male Wistar rats. Nine groups of rats were treated as follows: Group 1 was given 50 mg MNNG/liter and 6 g NaCl solution/liter to drink and was fed a stock diet supplemented with 10% NaCl. Group 2 received 1 ml saturated NaCl once a week and 50 mg MNNG/liter to drink. Group 3 was treated with MNNG alone. Group 4 was given a solution of 1 mg NQO once a week and fed a stock diet supplemented with 10% NaCl. Group 5 received a solution of 1 mg NQO saturated with NaCl. Group 6 was given NQO alone. Groups 7 and 8 were given NaCl alone. Group 9 was untreated. Adenocarcinomas developed in the glandular stomach in group 2 at a significantly higher incidence than in group 3. Poorly differentiated adenocarcinomas of the glandular stomach were detected in only groups 1 and 2. One poorly differentiated adenocarcinoma metastasized to the lymph nodes. A high incidence of squamous cell carcinomas of the forestomach was found in groups 4 and 5. No malignant tumors were seen in groups 6-9. NaCl given alone had no apparent carcinogenicity in rats but, when administered with MNNG or NQO, it enhanced the carcinogenic effects of MNNG and NQO in the stomach.

Sodium Intake, Salt Taste and Gastric Cancer Risk According to Helicobacter Pylori Infection, Smoking, Histological Type and Tumor Site in China

“…High salted food, such as processed meat, pickled vegetable or dried fish, whose consumption is used as a surrogate for salt exposure, also have a high content of nitrosated compounds. Ingestion of those high salted food could induce gastritis and coadministrate with N-methyl-Nnitro-N-nitrosoguanidine to enhance the carcinogenic effect of gastric carcinogens (Tatamatsu et al, 1975;Takahashi and Hasegawa, 1985). A high intragastric salt concentration could destroys the mucosal barrier, and leads to inflammation and damage such as diffuse erosion and degeneration.…”

Salt and salted food intake and subsequent risk of gastric cancer among middle-aged Japanese men and women

“…In experimental studies with rats, ingestion of salt is known to cause gastritis, and when coadministered, it enhances the carcinogenic effects of known gastric carcinogens such as Nmethyl-N-nitro-N-nitrosoguanidine (MNNG; Tatematsu et al, 1975;Takahashi and Hasegawa, 1985). Moreover, many epidemiological studies showed that salt or salted food intake increased the risk of gastric cancer (Kono and Hirohata, 1996), including those conducted among Japanese (Tajima and Tominaga, 1985;Hoshiyama and Sasaba, 1992;Tsugane et al, 1992b).…”

Diet and the risk of gastric cancer: review of epidemiological evidence

“…In experimental studies in rats, ingestion of salt is known to cause gastritis and, on co-administration, to enhance the carcinogenic effects of known gastric carcinogens such as N-methyl-N-nitro-N-nitrosoguanidine (MNNG) [8,9]. A high salt concentration in the stomach destroys the mucosal barrier and leads to infl ammation and damage such as diffuse erosion and degeneration.…”