Electric acupuncture stimulates non-parietal cell secretion of the stomach in dog

The effects of protein tyrosine kinase (PTK) activities on the modulation of secretion were investigated in isolated rabbit parietal cells. Two classes of inhibitors, genistein (an inhibitor of both soluble and membrane-associated PTK activities) and an erbstatin analogue (an inhibitor of membrane-associated PTK activities), were tested against both secretagogue stimulation as well as transforming growth factor-alpha (TGF-alpha) inhibition. Pretreatment of rabbit parietal cells with 10(-7) M rat TGF-alpha resulted in inhibition of both histamine- and carbachol-stimulated [14C]-aminopyrine (AP) accumulation. TGF-alpha inhibition was totally reversed by simultaneous pretreatment of cells with 50 microM genistein or an erbstatin analogue, indicating that a receptor-associated PTK activity is likely involved in the inhibition of parietal cell secretion. Furthermore, genistein, but not the erbstatin analogue, potentiated histamine-stimulated AP accumulation with a change in EC50 from 1.9 to 0.5 microM. Similarly, genistein, but not the erbstatin analogue, potentiated the response to forskolin with a change in EC50 from 1.5 to 0.1 microM. Genistein had no effect on stimulation of AP uptake by either dibutyryladenosine 3',5'-cyclic monophosphate or carbachol. In addition, genistein failed to increase histamine or forskolin stimulation beyond the maximal level and had no significant effect on either cellular adenosine 3',5'-cyclic monophosphate production or intracellular Ca2+ concentration. These results suggest that a PTK-protein phosphotyrosine phosphatase system may be involved in the potentiation of the histamine signal by a mechanism independent of adenylate cyclase activation.

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Ezrin-Acap4 Interaction Regulates Gastric Parietal Cell Secretion and Homeostasis

Gastroenterology ◽

10.1016/s0016-5085(17)31136-8 ◽

2017 ◽

Vol 152 (5) ◽

pp. S251

Author(s):

Xuebiao Yao ◽

Xing Liu ◽

William W. Yao

Keyword(s):

Parietal Cell ◽

Cell Secretion ◽

Gastric Parietal Cell

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Enrichment of rab11, a small GTP-binding protein, in gastric parietal cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1994.267.2.g187 ◽

1994 ◽

Vol 267 (2) ◽

pp. G187-G194 ◽

Cited By ~ 9

Author(s):

J. R. Goldenring ◽

C. J. Soroka ◽

K. R. Shen ◽

L. H. Tang ◽

W. Rodriguez ◽

...

Keyword(s):

Parietal Cell ◽

Binding Protein ◽

Polyclonal Antiserum ◽

Parietal Cells ◽

Cell Secretion ◽

Gtp Binding Protein ◽

Gtp Binding ◽

Target Membrane ◽

Gastric Parietal Cells ◽

Atpase Staining

Parietal cell secretion of acid requires the coordinated fusion of H(+)-K(+)-adenosinetriphosphatase (ATPase)-containing tubulovesicles with a secretory canalicular target membrane. We have previously reported the presence of rab2 on parietal cell tubulovesicles (L. H. Tang, S. A. Stoch, I. M. Modlin, and J. R. Goldenring. Biochem. J. 285: 715-719, 1992). Since 60% of the small GTP-binding protein sequences obtained from parietal cells were > 95% homologous with human rab11 (J. R. Goldenring, K. R. Shen, H. D. Vaughan, and I.M. Modlin. J. Biol. Chem. 268: 18419-18422, 1993), we sought to study rab11 in gastric parietal cells. A complete rab11 sequence was obtained, and the deduced amino acid sequence of rabbit rab11 was identical to that for human. Rab11 mRNA was present throughout the gastrointestinal mucosa. mRNA for both rab11 and rab2 were enriched in isolated parietal cells compared with chief cells. A polyclonal antiserum against rab11 labeled a single 25-kDa band in isolated parietal cells. Immunostaining of rat fundic tissue demonstrated prominent staining of parietal cells. Rab11 staining cosegregated with alpha-H(+)-K(+)-ATPase staining in enriched preparations of rabbit parietal cell tubulovesicles. These results suggest that rab11 is enriched in parietal cells and is associated with intracellular tubulovesicles.

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An inhibitor of Ca2+/calmodulin-dependent protein kinase II, KN-62, inhibits cholinergic-stimulated parietal cell secretion

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1992.262.1.g118 ◽

1992 ◽

Vol 262 (1) ◽

pp. G118-G122 ◽

Cited By ~ 6

Author(s):

Y. Tsunoda ◽

M. Funasaka ◽

I. M. Modlin ◽

H. Hidaka ◽

L. M. Fox ◽

...

Keyword(s):

Protein Kinase ◽

Parietal Cell ◽

Parietal Cells ◽

Cell Secretion ◽

Dependent Protein Kinase ◽

Protein Kinase Ii ◽

Dependent Protein ◽

High Concentrations ◽

Total Membrane

Cholinergic stimulation of parietal cell secretion is mediated by an increase in intracellular calcium. KN-62, a selective inhibitor of Ca2+/calmodulin-dependent protein kinase II (CaMK II), has recently been synthesized (Tokomitsu et al. J. Biol. Chem. 265: 4315-4320, 1990). To define the role of CaMK II in parietal cell secretion, we determined the effects of KN-62 on secretagogue-stimulated acid secretion in isolated rabbit parietal cells. Pretreatment of parietal cells with KN-62 resulted in the inhibition of carbachol-stimulated [14C]aminopyrine uptake over a concentration range of 3 to 60 microM (IC50 of 20 microM). KN-62 (60 microM) reduced carbachol-stimulated aminopyrine uptake to unstimulated levels. KN-62 did not alter carbachol-stimulated increases in cytoplasmic free Ca2+ concentration. High concentrations of KN-62 (60 microM) elicited a small decrease in aminopyrine uptake stimulated by forskolin, but did not significantly inhibit histamine stimulation. A potent CaMK II activity was identified in total membrane from parietal cells. These results suggest that CaMK II may mediate cholinergic-stimulated parietal cell secretion.

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