Enhancement by sulpiride of the inhibitory effects of cysteamine on gastric carcinogenesis induced by n-methyl-n'-nitro-n-nitrosoguanidine in wistar rats

✍ Scribed by Masaharu Tatsuta; Hiroyasu Iishi; Miyako Baba; Akihiko Nakaizumi; Hiroyuki Uehara; Haruo Taniguchi

• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: French
• Weight: 675 KB
• Volume: 47
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910470111

✦ Synopsis

The effects of sulpiride on cysteamine iyhibition of gastric carcinogenesis induced by N-methyl-N -nitro-N-nitrosoguanidine (MNNG) and on the BUdR labelling index of gastric mucosa were investigated in inbred Wistar rats. After 25 weeks of oral treatment with MNNG, rats received one of the following alternate-day injections: cysteamine (2 doses), cysteamine (2 doses) plus sulpiride or sulpiride. A t week 52, prolonged administration of cysteamine significantly reduced the incidence of adenocarcinornas of the glandular stomach. Cysteamine at low dose had no effect on the incidence of gastric cancers, but a combination of low-dose cysteamine and sulpiride caused a significantly greater reduction in the incidence of gastric cancers. Administration of sulpiride alone had no influence on gastric carcinogenesis. The labelling index of the antral mucosa was significantly lower in rats treated with high but not low doses of cysteamine. However, a cornbination of low-dose cystearnine and sulpiride significantly decreased the labelling index of the antral mucosa. Our findings indicate that cysteamine suppressed gastric carcinogenesis and that sulpiride enhanced this inhibition. Because sulpiride is a doparnine antagonist, these findings also indicate that dopamine may play an important role in cysteamine inhibition of gastric carcinogenesis.