Somatostatin inhibits pepsinogen secretion without influencing cytosolic free Ca2+ increase induced by carbachol and cholecystokinin octapeptide in rat chief cells.
Gastric chief cells were isolated from the rat stomach in an attempt to identify those involved in the mechanism of action of somatostatin on pepsinogen secretion. The effects of several kinds of secretagogues on cytosolic free Ca2+ concentration ([Ca2+]i) were examined in the rat chief cells. Carbachol and cholecystokinin octapeptide (CCK-8) markedly induced [Ca2+]i increase, while histamine, gastrin I and secretin did not. Carbachol and CCK-8 also stimulated pepsinogen secretion. A similar dose-response relationship was seen in carbachol- and CCK-8-induced [Ca2+]i increase and pepsinogen secretion. Somatostatin did not inhibit carbachol- or CCK-8-induced [Ca2+]i increase, but did inhibit carbachol- and CCK-8-induced pepsinogen secretion by 30 and 50%, respectively.
Tanaka
T
T
Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan.
Miyadera
K
K
Tani
S
S
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology*; D002478:Cells, Cultured; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism*; D005753:Gastric Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010435:Pepsinogens / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000494:pharmacology*; D013004:Somatostatin / Q000494:pharmacology*
D010435:Pepsinogens; D013004:Somatostatin; D002217:Carbachol; D012844:Sincalide; D002118:Calcium