ROLE OF BLOOD-FLOW IN PROTECTION AGAINST PENETRATION OF CARCINOGENS INTO NORMAL AND HEALING RAT GASTRIC-MUCOSA

The effects of intragastric capsaicin and gastric artery ligation on t he penetration of the gastric carcinogen N[methyl-H-3]-N'-nitro-N-nitr osoguanidine ([H-3]MNNG) to proliferative cells were studied in normal and healing rat gastric mucosa. The percentage of S-phase cells label ed with [H-3]MNNG in normal corpus mucosa was higher (7.0 +/- 2.0%) af ter gastric artery ligation than in controls with intact blood flow (2 .7 +/- 1.0%) and in animals treated with capsaicin (1.8 +/- 0.5%). Cor pus mucosal blood flow was correlated with the percentage of S-phase c ells labeled with [H-3] MNNG in normal controls and in capsaicin-treat ed animals. In healing corpus mucosa and in the antrum, capsaicin or g astric artery ligation did not affect carcinogen penetration. We concl ude that blood flow protects against penetration of carcinogens to pro liferative cells in normal corpus mucosa but not in the antrum. Low mu cosal blood flow in the corpus could be a risk factor for initiation o f gastric carcinogenesis.