AJP - Gastrointestinal and Liver Physiology, Vol 262, Issue 1 69-G73, Copyright © 1992 by American Physiological Society
Distribution of smg p25A and smg p21s, ras p21-like guanine nucleotide-binding proteins, in the rat stomach
K. Matsuda, C. Sakamoto, O. Nakano, Y. Konda, T. Matozaki, K. Wada, M. Kasuga, A. Mizoguchi, A. Kikuchi and Y. Takai
Second Department of Internal Medicine, Kobe University School of Medicine, Japan.
Existence and distribution of small guanine nucleotide binding proteins (G
proteins) such as smg p25A, smg p21s, and ras p21s were examined in the rat
gastric mucosa. By immunoblot analysis using the specific monoclonal
antibodies against smg p25A and ras p21 and the anti-smg p21 antiserum, smg
p25A and smg p21s were detected in the gastric mucosa, while ras p21s were
not detected. In immunocytochemical studies, moderate fluorescence of smg
p25A was homogenously seen in the cytoplasmic portions of chief cells and
surface epithelial cells. smg p21 immunoreactivity was detected in
glandular cells and submucosal muscle layer in the mucosa. On the other
hand, the cells constituting gastric glands were unstained with the
anti-ras p21 monoclonal antibody, RASK-4. These results suggest that smg
p25A and smg p21s exist as in other tissues and might exert their specific
actions in the rat gastric mucosa.
