Epithelial cell proliferation in the digestive tract induced by space restriction and water-immersion stress.
The effects of space restriction and water-immersion stress on epithelial cell proliferation in the digestive tract, with special attention to the esophagus, stomach and duodenum, in 8-week-old SD male rats were examined. Histological assessment revealed spotted hemorrhagic lesions in the fundus of the glandular stomach, accompanied by statistically increased 5-bromo-2'-deoxyuridine (BrdU) labeling index in the fundic and pyloric regions. Furthermore, biochemical analysis demonstrated an increased activity of ornithine decarboxylase (ODC) and spermidine/spermine N1-acetyltransferase (SAT), known as key late-limiting enzymes of the polyamine pathway, in the gastric fundus. The stress may induce a remarkable increase in expression of c-fos, c-jun and c-myc mRNAs in both fundic and pyloric regions of the glandular stomach. There were no remarkable changes in the esophagus. These results indicate that space restriction and water-immersion stress induced cell proliferation in the glandular stomach through overexpression of proto-oncogenes and increased ODC and SAT activities that might be related to the promotion of gastric carcinogenesis.
Hori
T
T
First Department of Pathology, Osaka City University Medical School, Osaka, Japan.
Wanibuchi
H
H
Yano
Y
Y
Otani
S
S
Nishikawa
A
A
Osugi
H
H
Kinoshita
H
H
Fukushima
S
S
D000123:Acetyltransferases / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D017209:Apoptosis; D001973:Bromodeoxyuridine / Q000378:metabolism; D002455:Cell Division; D004386:Duodenum / Q000473:pathology*; D004847:Epithelial Cells; D004947:Esophagus / Q000473:pathology*; D008297:Male; D009955:Ornithine Decarboxylase / Q000378:metabolism; D011519:Proto-Oncogenes; D051381:Rats; D017207:Rats, Sprague-Dawley; D013270:Stomach / Q000473:pathology*; D013312:Stress, Physiological / Q000473:pathology*; D000099228:Diamine N-Acetyltransferase
D000123:Acetyltransferases; D000324:Adrenocorticotropic Hormone; D001973:Bromodeoxyuridine; D009955:Ornithine Decarboxylase; D000099228:Diamine N-Acetyltransferase