The effects of H.pylori and its crude extracted proteins on isolated rabbit parietal cells acid secretion
- VernacularTitle:幽门螺杆菌及其培养上清液粗提蛋白对兔离体胃壁细胞酸分泌的影响
- Author:
Tao GUO
;
Yuqing ZHAO
;
Jiaming QIAN
;
Xiaobo LI
;
Jianzhong ZHANG
- Publication Type:Journal Article
- Keywords:
Parietal cells,gastric;
Helicobacter pylori;
Vacuolating cytotoxin;
Acid secretion;
H+-K+ ATPase
- From:
Chinese Journal of Internal Medicine
2008;47(7):566-569
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effects of H.pylori and crude extracted proteins secreted by H.pylori(broth culture filtrate protein,BCF-P)on acid secretion from isolated rabbit parietal cells.Methods Parietal cells from rabbit gastric mucosa were isolated and enriched with digestion and elutriation.H.pylori(NCTC 11637,CagA+ VacA+)were grown in liquid broth culture and BCF-P was precipitated with ammonium sulfate.The vacuolation activity of BCF-P was evaluated with neutral red dye uptake test in HeLa cell.Isolated parietal cells were incubated with H.pylori(bacteria/cell=100∶1)for 2 h and 16 h,or BCF-P(100μg/ml)for 1 h and 12 h.Acid secretion from parietal cells was studied using 14C-aminopyrine(14C-AP)accumulation indirectly and H+-K+ ATPase α subunit mRNA expression was assessed using RT-PCR.Results (1)BCF-P containing vacuolating cytotoxin(VacA)with vacuolation activity on HeLa cells had positive result on neutral red uptake test.(2)The basal expression of H+-K+ ATPase α subunit mRNA could be detected in isolated parietal cells and 14C-AP accumulation was significantly increased in response to the stimulation of histamine with different concentrations for 30 min(P＜0.05).These results indicated that the isolated parietal cells retain relative intact acid secretion function.(3)The histamine(1.0×104 mol/L)stimulated acid secretion was inhibited sustainedly in response to H.pylori by 81% at 2 h and by 94% at 16 h(P＜0.05).However,H+-K+ ATPase α subunit mRNA expression was up-regulated in tlle acute period(2 h)and was down-regulated in the chronic period (16 h)by H.pylori(P＜0.05).(4)BCF-P significantly inhibited the histamine-stimulated acid secretion by 24% at 1 h and by 58% at 12 h(P＜0.05),and this inhibition was accompanied by the down-regulated expression of H+-K+ATPase α subunit mRNA.Conclusions Intact H.pylori and VacA secreted by H.pylori could directly inhibit histamine-stimulated acid secretion from parietal cells and this inhibition may be mediated by the down-regulated H+-K+ ATPase expression.
