Serum and antral gastrin levels in fed and fasted rats: relation to aging.
The effect of short fasting for up to 24 h on serum and antral gastrin concentrations and G cell ultrastructure has been examined in the young rat compared with the middle-aged rat. The serum gastrin levels at 24-h fasting were markedly reduced in both young and middle-aged rats. There was also a significant decrease in antral gastrin concentrations after 24 h of fasting in the middle-aged rats. By contrast, the antral gastrin concentrations in the young rats increased progressively and significantly with fasting for up to 24 h. These responses were associated with a significant increase in the content of secretory granules of G cell, which was at its greatest by 24 h. The antral gastrin level in the 48-h fasting rats was markedly reduced to a level below that for the prestarvation group. By 48 h of starvation, the amount of secretory granules in G cell was significantly reduced (P < 0.05) compared with the 24-h fasting group. These results indicate that the effects of fasting on the antral gastrin levels in young rats differ from those of the middle-aged and that starvation for up to 24 h caused a significant increase in the antral gastrin content in the young rats' stomach.
Ichikawa
T
T
Department of Biochemistry, Kitasato University School of Medicine, Kanagawa, Japan. t.ichika@medcc.kitasato-u.ac.jp
Ishihara
K
K
Nozue
K
K
Miyazawa
S
S
Nemoto
N
N
Hotta
K
K
D000375:Aging / Q000097:blood / Q000378:metabolism*; D000818:Animals; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D005215:Fasting / Q000097:blood / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism* / Q000648:ultrastructure; D005755:Gastrins / Q000097:blood* / Q000378:metabolism*; D008297:Male; D008854:Microscopy, Electron; D011706:Pyloric Antrum / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar