Role of Na + / H + exchange and HCO 3 − transport in pH i recovery from intracellular acid load in cultured epithelial cells of sheep rumen

2000 ◽  
Vol 170 (4) ◽  
pp. 337-343 ◽  
Author(s):  
F. Müller ◽  
J. R. Aschenbach ◽  
G. Gäbel
Keyword(s):  
Epithelial Cells ◽  
Cultured Epithelial Cells ◽  
Acid Load ◽  
Sheep Rumen ◽  
Intracellular Acid

A vH+-ATPase is present in cultured sheep ruminal epithelial cells

2006 ◽  
Vol 291 (6) ◽  
pp. G1171-G1179 ◽  
Author(s):  
Benjamin Etschmann ◽  
Katrin Sophie Heipertz ◽  
Annabelle von der Schulenburg ◽  
Monika Schweigel
Keyword(s):  
Epithelial Cells ◽  
Primary Cultures ◽  
Selective Inhibition ◽  
Protein Band ◽  
Inhibitory Effect ◽  
B Subunit ◽  
Initial Ph ◽  
Acid Load ◽  
Acid Loading

In this study, the existence and functional activity of a vacuolar-type H+-ATPase (vH+-ATPase) was explored in primary cultures of sheep ruminal epithelial cells (REC). The mRNA transcripts of the E and B subunits of vH+-ATPase were detectable in RNA from REC samples by RT-PCR. Immunoblotting of REC protein extractions with antibodies directed against the B subunit of yeast vH+-ATPase revealed a protein band of the expected size (60 kDa). Using the fluorescent indicator BCECF and selective inhibitors (foliomycin, HOE 694, S3226), the contribution of vH+-ATPase and Na+/H+ exchanger (NHE) subtype 1 and 3 activity to the regulation of intracellular pH (pHi) was determined in nominally HCO3−-free, HEPES-buffered NaCl medium containing 20 mM of the short-chain fatty acid butyrate as well as after reduction of the extracellular Cl− concentration ([Cl−]e) from 136 to 36 mM. The initial pHi of REC was 7.4 ± 0.1 in nominally HCO3−-free, HEPES-buffered NaCl medium and 7.0 ± 0.1 after acid loading with butyrate. Selective inhibition of the vH+-ATPase with foliomycin decreased pHi by 0.19 ± 0.03 pH units. On the basis of the observed decreases in pHi resulting from inhibition of vH+-ATPase as well as of subtypes 1 and 3 of NHE, vH+-ATPase activity appears to account for ∼30% of H+ extrusion, whereas the activities of NHE subtypes 3 and 1 account for 20 and 50% of H+ extrusion, respectively. Lowering of [Cl−]e induced a pHi decrease (−0.51 ± 0.03 pH units) and impaired pHi recovery from butyrate-induced acid load. Moreover, reduction of [Cl−]e abolished the inhibitory effect of foliomycin and markedly reduced the HOE 694- and S3226-sensitive components of pHi, indicating a role of Cl− in the function of these H+ extrusion mechanisms. We conclude that a vH+-ATPase is expressed in ovine REC and plays a considerable role in the pHi regulation of these cells.

Localization and distribution of angiotensin II in the rat epididymis

1996 ◽  
Vol 149 (2) ◽  
pp. 217-222 ◽  
Author(s):  
W Zhao ◽  
P Y Leung ◽  
S B Cheng Chew ◽  
H C Chan ◽  
P Y D Wong
Keyword(s):  
Angiotensin Ii ◽  
Epithelial Cells ◽  
Culture Medium ◽  
Epithelial Transport ◽  
Apical Region ◽  
Basal Region ◽  
Ang Ii ◽  
Cultured Epithelial Cells ◽  
Rat Epididymis

Abstract The localization and distribution of angiotensin II (Ang II) in the rat epididymis was studied using immunohistochemical and RIA techniques. The immunohistochemical results showed that Ang II-like immunoreactivity progressively increased along the length of the rat epididymis (cauda>corpus>>caput) and was predominately localized in the basal region of the epididymal epithelium. Occasionally, immunostaining of lighter intensity was also found in the apical region. The concentration of Ang II in cultured rat cauda epididymal epithelial cells was further measured by RIA. In addition to that found in cultured epithelial cells, Ang II activity was also detected in the culture medium, suggesting a secretory role of the epithelium. These findings suggest that Ang II could be derived locally from epididymal epithelium and that it could play a role in local regulation of epithelial transport and, possibly, in the maintenance of sperm function as well, by exerting its paracrine and/or autocrine effect in various regions of the epididymis. Journal of Endocrinology (1996) 149, 217–222

TRPV4-Mediated Epithelial Junction Disruption in Allergic Rhinitis Triggered by House Dust Mites

2020 ◽  
pp. 194589242096416
Author(s):  
Kijeong Lee ◽  
Junhyoung Byun ◽  
Byoungjae Kim ◽  
Jiwoo Yeon ◽  
Junhu Tai ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
House Dust ◽  
Nasal Epithelial Cells ◽  
Zonula Occludens ◽  
Dust Mite ◽  
Cultured Epithelial Cells ◽  
Junctional Protein ◽  
Der P 1 ◽  
Zonula Occludens 1

Background Epithelial barrier disruption is a crucial feature of allergic rhinitis (AR). Previous reports have indicated the role of transient receptor potential vanilloid (TRPV) 4 in regulating the intercellular junctions in various cells. However, the role of TRPV4 and its regulation by T helper 2 cell cytokines in the epithelial cells of patients with AR remains unclear. Objective We aimed to elucidate the expression of TRPV4 in nasal epithelial cells and its cytokine-induced regulation, and to reveal its role in house dust mite-induced junction disruption in AR. Methods The expression of TRPV4 in nasal epithelial cells was measured using real-time polymerase chain reaction, western blot, and immunohistochemical assays, and the expression levels were compared between the patients with AR and healthy controls. Altered expression of TRPV4 was induced in cultured nasal epithelial cells by stimulation of interleukin (IL) 4, IL-13, and tumor necrosis factor alpha. In addition, expression of E-cadherin and zonula occludens 1 was induced in Der p 1-stimulated epithelial cells by treatment with either a TRPV4 agonist (GSK1016790A) or a TRPV4 antagonist (RN1734). Results TRPV4 expression was increased in epithelial cells harvested from the affected turbinates compared to those from the normal turbinates. The stimulation of cultured epithelial cells with IL-4 and IL-13 resulted in TRPV4 upregulation. Additionally, E-cadherin and zonula occludens 1 expression levels decreased in the cultured epithelial cells treated with GSK1016790A after stimulation with Der p 1, whereas Der p 1 stimulation alone showed no effect on junctional protein expression. Conclusions Increased TRPV4 expression occurred in epithelial cells harvested from patients with AR and epithelial cells stimulated by Th2 cytokines. Decreased junctional protein expression in epithelial cells after the stimulation by house dust mite allergen with TRPV4 agonist indicates a possible role of TRPV4 in the pathogenesis of allergen-induced epithelial barrier disruption in AR.

ATP-sensitive Na(+)-H+ antiport in type II alveolar epithelial cells

1991 ◽  
Vol 261 (6) ◽  
pp. C954-C963 ◽  
Author(s):  
S. E. Brown ◽  
T. A. Heming ◽  
C. R. Benedict ◽  
A. Bidani
Keyword(s):  
Epithelial Cells ◽  
Alveolar Epithelial Cells ◽  
Type Ii Cells ◽  
Type Ii ◽  
Cell Monolayers ◽  
Sulfhydryl Reagent ◽  
Alveolar Epithelial ◽  
Acid Load ◽  
Type Ii Cell ◽  
Intracellular Acid

Type II alveolar epithelial cells in suspension have been previously shown to possess a Na(+)-H+ antiporter that modulates recovery from an intracellular acid load in the nominal absence of HCO-3 [E. Nord, S. Brown, and E. Crandall. Am. J. Physiol. 252 (Cell Physiol. 21): C490-C498, 1987]. Such a Na(+)-dependent mechanism has also been demonstrated in cultured type II cell monolayers (K. Sano et al. Biochim. Biophys. Acta 939: 449-458, 1988). It has recently been suggested that cultured type II cells possess a H(+)-ATPase that contributes to recovery from an intracellular acid load [R. Lubman, S. Danto, and E. Crandall. Am. J. Physiol. 257 (Lung Cell. Mol. Physiol. 1): L438-L445, 1989]. The present study was undertaken to investigate and characterize the mechanisms by which cultured type II cells recover from an intracellular acid load in the nominal absence of HCO-3. Cultured type II cell monolayers were loaded with the pH-sensitive probe 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein, and the characteristics of recovery from an imposed intracellular acid load were studied. Recovery of intracellular pH (pHi) was found to be strictly Na(+)-dependent and inhibited greater than or equal to 95% by 1 mM amiloride. Initial rate of recovery was highly sensitive to pHi, with recovery rates varying inversely with increasing pHi. An acidic extracellular pH (6.5) abolished pHi recovery. Treatment of type II cells with either the sulfhydryl reagent N-ethylmaleimide, a nonspecific sulfhydryl reagent, or 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole, a specific vacuolar H(+)-ATPase inhibitor at the concentration tested, resulted in marginal but not statistically significant decrements in pHi recovery. Intracellular ATP depletion, using KCN or replacement of glucose by a nonmetabolizable glucose analogue, reduced pHi recovery by 70-75% relative to control values. Sensitivity to ATP was apparent even under conditions that preserved the transmembrane Na+ gradient. Taken together, these data are most consistent with a single mechanism for pHi recovery in the absence of HCO3-. We interpret this mechanism to be an ATP-sensitive Na(+)-H+ antiporter that acts to reestablish pHi in type II alveolar epithelial cells.

Cocaine Increases Sendai Virus Replication in Cultured Epithelial Cells: Critical Role of the Intracellular Redox Status

1996 ◽  
Vol 228 (2) ◽  
pp. 579-585 ◽  
Author(s):  
Anna T. Palamara ◽  
Paolo Di Francesco ◽  
Maria R. Ciriolo ◽  
Cristina Buè ◽  
Emanuela Lafavia ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Virus Replication ◽  
Sendai Virus ◽  
Critical Role ◽  
Redox Status ◽  
Cultured Epithelial Cells ◽  
Intracellular Redox Status ◽  
Intracellular Redox

scholarly journals O-Linked Glycosylation Ensures the Normal Conformation of the Autotransporter Adhesin Involved in Diffuse Adherence

2007 ◽  
Vol 189 (24) ◽  
pp. 8880-8889 ◽  
Author(s):  
Marie-Ève Charbonneau ◽  
Victoria Girard ◽  
Anastasia Nikolakakis ◽  
Manuel Campos ◽  
Frédéric Berthiaume ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Escherichia Coli ◽  
Epithelial Cells ◽  
Heat Extraction ◽  
Cell Binding ◽  
Binding Function ◽  
Cultured Epithelial Cells ◽  
First Time

ABSTRACT The Escherichia coli adhesin involved in diffuse adherence (AIDA-I) is one of the few glycosylated proteins found in Escherichia coli. Glycosylation is mediated by a specific heptosyltransferase encoded by the aah gene, but little is known about the role of this modification and the mechanism involved. In this study, we identified several peptides of AIDA-I modified by the addition of heptoses by use of mass spectrometry and N-terminal sequencing of proteolytic fragments of AIDA-I. One threonine and 15 serine residues were identified as bearing heptoses, thus demonstrating for the first time that AIDA-I is O-glycosylated. We observed that unglycosylated AIDA-I is expressed in smaller amounts than its glycosylated counterpart and shows extensive signs of degradation upon heat extraction. We also observed that unglycosylated AIDA-I is more sensitive to proteases and induces important extracytoplasmic stress. Lastly, as was previously shown, we noted that glycosylation is required for AIDA-I to mediate adhesion to cultured epithelial cells, but purified mature AIDA-I fused to GST was found to bind in vitro to cells whether or not it was glycosylated. Taken together, our results suggest that glycosylation is required to ensure a normal conformation of AIDA-I and may be only indirectly necessary for its cell-binding function.

Effect of Calcium on the Growth and Differentiation of Cultured Rat Esophageal Epithelial Cells

1982 ◽  
Vol 40 ◽  
pp. 132-133
Author(s):  
W.T. Gunning ◽  
M.R. Marino ◽  
M.S. Babcock ◽  
G.D. Stoner
Keyword(s):  
Epithelial Cells ◽  
Cell Types ◽  
Replication Rate ◽  
Enzymatic Dissociation ◽  
Growth Assay ◽  
Epidermal Growth ◽  
Fetal Bovine ◽  
Esophageal Epithelial Cells ◽  
Cellular Replication

The role of calcium in modulating cellular replication and differentiation has been described for various cell types. In the present study, the effects of Ca++ on the growth and differentiation of cultured rat esophageal epithelial cells was investigated.Epithelial cells were isolated from esophagi taken from 8 week-old male CDF rats by the enzymatic dissociation method of Kaighn. The cells were cultured in PFMR-4 medium supplemented with 0.25 mg/ml dialyzed fetal bovine serum, 5 ng/ml epidermal growth factor, 10-6 M hydrocortisone 10-6 M phosphoethanolamine, 10-6 M ethanolamine, 5 pg/ml insulin, 5 ng/ml transferrin, 10 ng/ml cholera toxin and 50 ng/ml garamycin at 36.5°C in a humidified atmosphere of 3% CO2 in air. At weekly intervals, the cells were subcultured with a solution containing 1% polyvinylpyrrolidone, 0.01% EGTA, and 0.05% trypsin. After various passages, the replication rate of the cells in PFMR-4 medium containing from 10-6 M to 10-3 M Ca++ was determined using a clonal growth assay.

Role of Bronchial Epithelial Cells in Pathogenesis of COPD

Pneumologie ◽  
2011 ◽  
Vol 65 (12) ◽  
Author(s):  
S Rim ◽  
S Jahan ◽  
G John ◽  
K Kohse ◽  
A Bohla ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Bronchial Epithelial Cells ◽  
Bronchial Epithelial

Vimentin organizing centre in cultured epithelial cells

Pathology ◽  
1984 ◽  
Vol 16 (4) ◽  
pp. 393-395 ◽  
Author(s):  
John S. Pedersen ◽  
J.R. Underwood ◽  
B.H. Toh
Keyword(s):  
Epithelial Cells ◽  
Cultured Epithelial Cells
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