Is the ClC-2 chloride channel involved in the Cl- secretory mechanism of gastric parietal cells?
It has been controversial whether the ClC-2 chloride channel is involved in hydrochloric acid secretion of gastric parietal cells. Here, we investigated whether ClC-2 is the apical Cl- channel associated with gastric acid secretion. Two anti-ClC-2 antibodies used in this study reacted with cloned ClC-2 protein expressed in HEK293 cells. In isolated rabbit gastric glands, significant expression of ClC-2 mRNA was observed, but the presence of ClC-2 protein was not clear. Furthermore, no expression of ClC-2 protein was observed in isolated rat and human gastric mucosa. Immunohistochemistry on the rat gastric mucosa showed no significant expression of ClC-2 protein in the parietal cells which showed abundant expression of H+,K+-ATPase. These results indicate that ClC-2 may not be a Cl- -transporting protein for gastric acid secretion in parietal cells.
Hori
Katsuhito
K
Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan.
Takahashi
Yuji
Y
Horikawa
Naoki
N
Furukawa
Tetsushi
T
Tsukada
Kazuhiro
K
Takeguchi
Noriaki
N
Sakai
Hideki
H
D000368:Aged; D000818:Animals; D000090007:CLC-2 Chloride Channels; D002460:Cell Line; D018118:Chloride Channels / Q000235:genetics / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism*; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000166:cytology / Q000378:metabolism; D017506:H(+)-K(+)-Exchanging ATPase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010295:Parietal Cells, Gastric / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D013270:Stomach / Q000033:anatomy & histology
D000090007:CLC-2 Chloride Channels; D018118:Chloride Channels; D002712:Chlorides; D012333:RNA, Messenger; D017506:H(+)-K(+)-Exchanging ATPase