title: Synergism between sodium chloride and sodium taurocholate and development of pepsinogen-altered pyloric glands: relevance to a medium-term bioassay system for gastric carcinogens and promoters in rats.
abstract: In an approach to early detection of gastric carcinogens and promoters in an in vivo test system, promotion by sodium chloride (NaCl) and the synergistic effects of NaCl and sodium taurocholate (Na-TC) on development of pepsinogen-altered pyloric glands (PAPG) in rat glandular stomach after initiation with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated. A total of 205 male WKY/NCrj rats were divided into 8 groups. Group 1 was given a single dose of MNNG of 160 mg/kg body weight by gastric intubation, and starting 2 weeks later basal diet containing Na-TC for 18 weeks. In addition, 1 ml doses of saturated NaCl solution were given by gastric intubation at weeks 4, 6, 8 and 10. Similarly, group 2 was treated with MNNG and Na-TC, while group 3 animals received MNNG and NaCl. Group 4 was given MNNG alone. Groups 5-8 served as equivalent controls without MNNG initiation. The results revealed significantly enhanced induction of immunohistochemically defined PAPG in the Na-TC + NaCl (P less than 0.001), Na-TC (P less than 0.01) and NaCl (P less than 0.01) treated animals initiated with MNNG. Sodium chloride demonstrated a clear synergistic effect with Na-TC in promoting the development of PAPG, suggesting possible advantage for its use in medium-term in vivo assays for detection of gastric carcinogens and promoters.
authors.affiliation: First Department of Pathology, Nagoya City University Medical School.
authors.forename: M
authors.initials: M
authors.lastname: Tatematsu
authors.forename: M
authors.initials: M
authors.lastname: Mutai
authors.forename: K
authors.initials: K
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Ozaki
authors.forename: C
authors.initials: C
authors.lastname: Furihata
authors.forename: N
authors.initials: N
authors.lastname: Ito
mesh_terms: D000818:Animals; D001681:Biological Assay; D002273:Carcinogens; D004357:Drug Synergism; D005753:Gastric Mucosa / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008297:Male; D008769:Methylnitronitrosoguanidine; D010435:Pepsinogens / Q000032:analysis*; D051381:Rats; D011921:Rats, Inbred WKY; D012965:Sodium Chloride / Q000633:toxicity*; D013274:Stomach Neoplasms / Q000139:chemically induced*; D013656:Taurocholic Acid / Q000633:toxicity*
chemical_list: D002273:Carcinogens; D010435:Pepsinogens; D008769:Methylnitronitrosoguanidine; D012965:Sodium Chloride; D013656:Taurocholic Acid