In vitroeffects of ghrelin on gastric H+-K+-ATPase and pepsin activity and mRNA expression of gastrin, somatostatin, receptors for GH and IGF-1 in cultured gastric mucosal cells of weanling piglets

Abstract

AbstractThe present study was conducted to investigate the effects of ghrelin on gastric acid and pepsin secretion, as well as the mRNA expression of gastrin, somatostatin (SS) and receptors for growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in gastric mucosal cells in vitro. Gastric mucosal cells were isolated from 5-week-old weanling piglets and exposed for 4 h to 3×10−2, 3×10−1, 3, 3×10 and 3×102nmol/l of h-ghrelin, respectively after 30-h incubation in DMEM/F-12. Pepsin activity in culture medium, cell viability and H+-K+-ATPase activity, as well as mRNA expression of gastrin, SS, GHR and IGF-1R in gastric mucosal cells were determined as response criteria. The experiment was repeated three times. Ghrelin significantly (P<0·05) increased H+-K+-ATPase activity of gastric mucosal cells at 3×10−1, 3 and 3×10 nmol/l of h-ghrelin. However, no significant changes were observed either in pepsin activity or the cell viability after ghrelin treatment. The mRNA expression of gastrin and SS was significantly increased in gastric mucosal cells exposed to h-ghrelin at 3×10−1and 3 nmol/l (P<0·05). H-ghrelin significantly increased IGF-1R but not GHR mRNA expression at 3×10−1, 3 and 3×10 nmol/l of h-ghrelin (P<0·05). Ghrelin acts on gastric mucosal cells from weanling piglets to regulate the H+-K+-ATPase activity and mRNA expression of gastrin, SS, and IGF-1Rin vitro.