[Influence of Helicobacter pylori lipopolysaccharide on the function of enterochromaffin-like cells in vitro].
OBJECTIVE
To investigate the relationship between Helicobacter pylori (Hp) infection and pathophysiology of abnormal gastric acid secretion and mucosal proliferation by studying the effect of Hp lipopolysaccharide (LPS) on the function of enterochromaffin-like (ECL) cells in vitro.


METHODS
Pure isolated ECL cell preparation with a purity of +/- 95% was developed by proteinase digestion, elutriation and density gradient centrifugation with viability of > 95% as determined by trypan blue exclusion. After a short duration of culture basal and stimulated histamine secretion and DNA synthesis of ECL cells were measured by enzyme immunoassay and bromodeoxyuridine (BrdU) uptake, respectively.


RESULTS
Hp LPS stimulated basal and gastrin-stimulated histamine secretion (EC(50)4 x 10(-11) mol/L and EC(50) 10(-10) mol/L respectively). These effects were completely inhibited by somatostatin (10(-10) mol/L) but not by gastrin receptor antagonist L(365 260). Hp LPS did not stimulate basal DNA synthesis but significantly increased gastrin stimulated BrdU uptake with EC(50) of 10(-10) mol/L. Escherichia coil LPS had no significant effect on both histamine secretion and DNA synthesis.


CONCLUSIONS
Hp stimulates both ECL cell proliferation and secretion in vitro. An interaction between Hp LPS and ECL cells may contribute to the reported abnormalities in acid secretion and gastric pathophysiology noted in Hp infection.
Miu
K
K
Section of Digestive Disease, Department of Internal Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029.
Sun
L
L
Tang
L H
LH
Modlin
I M
IM
D000818:Animals; D002478:Cells, Cultured; D004759:Enterochromaffin Cells / Q000502:physiology*; D005260:Female; D005744:Gastric Acid / Q000378:metabolism; D005753:Gastric Mucosa / Q000473:pathology; D016481:Helicobacter Infections / Q000503:physiopathology*; D016480:Helicobacter pylori; D006636:Histamine Release; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D008070:Lipopolysaccharides