No abstract available.
Animal ; Chloride Channels/metabolism ; Chloride Channels/biosynthesis* ; Choroid Plexus/metabolism* ; Choroid Plexus/cytology ; Epithelial Cells/metabolism*

It has been shown that a lot of diseases were related with the change or loss of Cl- channel functions. Among the Cl- channels, volume-regulated anion channel (VRAC) plays important roles in myocardial ischemia/reperfusion injury, cardiac arrhythmia and apoptosis; it may become a new target in the clinical treatment of heart diseases. This paper presents an overview of the physiological characteristics of VRAC and its relations with myocardial ischemia/reperfusion injury.
Chloride Channels ; classification ; metabolism ; physiology ; Humans ; Myocardial Reperfusion Injury ; metabolism

Cl(-) channel has been identified in heart over more than a decade. It is now known that Cl(-) channel is a super-family. The potentially important roles of cardiac Cl(-) channels have been emerging. Cardiac Cl(-) channels may play multifunctional roles in both physiological and pathophysiological conditions. Since the existence and distribution of cardiac Cl(-) channels vary with species and cardiac tissues, and blockade of Cl (-) channel with putative Cl(-) channel blockers or Cl(-) substitution has profound influence on cardiac electrical properties, it appears that the main role of cardiac Cl(-) channels may be to modulate cation channels or provide an ionic environment suitable for the activities of cation channels. So, to investigate the relationship between Cl(-) channels and cation channels may be of physiological and pathophysiological significance.
Animals ; Calcium Channels ; physiology ; Cations ; metabolism ; Chloride Channels ; physiology ; Heart ; physiology ; Humans ; Potassium Channels ; physiology ; Sodium Channels ; physiology ; TRPM Cation Channels ; physiology

In pancreatic acinar cells Ca(2+)-dependent secretagogues promote the fusion of zymogen granules (ZG) with the apical plasma membrane (PM) and exocytosis of digestive enzymes. In addition to exocytotic fusion complexes between SNARE proteins in the ZG membrane (ZGM) and the apical PM, enzyme secretion elicited by Ca(2+)-dependent secretagogues requires cytosolic Cl and K+ and is inhibited by blockers of Cl- and K+-channels. We have identified a Cl-conductance activated by ATP, and a K+-conductance (with properties similar to ATP-sensitive K+-channels), regulated by the granule matrix protein Zg-16p in the ZGM. Both conductances are inversely regulated by a 65-kD mdr1 gene product. We have also identified a novel Ca(2+)-activated anion conductance in ZGM, the Ca(2+)-sensitivity of which increases 50-fold when Cl is replaced by 1. This conductance is blocked by micromolar H2-DIDS or DTT, reminiscent of a family of epithelial Ca(2+)-activated Cl -channels (CaCC). Expression of a CaCC in exocrine pancreas has been confirmed by RT-PCR analysis, and by immunoblotting and immunogold labeling of ZG membranes. These data suggest that ion channels in the ZGM are essential elements in pancreatic exocytosis.
Animal ; Chloride Channels/metabolism* ; Chloride Channels/genetics ; Exocytosis/physiology* ; Gene Expression/physiology ; P-Glycoprotein/metabolism ; P-Glycoprotein/genetics ; Pancreas/secretion* ; Pancreas/cytology ; Potassium Channels/metabolism* ; Potassium Channels/genetics ; Secretory Vesicles/secretion ; Secretory Vesicles/metabolism* ; Support, U.S. Gov't, P.H.S.

Animals ; Cell Line ; Chloride Channels ; metabolism ; Epithelial Cells ; metabolism ; Escherichia coli ; metabolism ; Kidney ; cytology ; Osmotic Pressure ; Periplasm ; metabolism ; Swine

AIMTo observe the regulatory volume decrease (RVD) process of human intestine cells and investigate its ion channel mechanism.

METHODSCultured human intestine cells were exposed to hypotonic solution and the cell volume was measured using Coulter Counter System. RT-PCR was explored to detect the mRNA expression of Ca(2+) -activated K+ channel.

RESULTSHuman intestine cells showed a RVD process and this process could be blocked by Cl- channel blocker NPPB and K+ channel blocker TEA. Further results demonstrated the subtype of K+ channel involved in RVD was an intermediate-conductance, Ca(2+) -activated K+ channel (IK) because of its high sensitivity to clotrimazole. RT-PCR results also showed the expression of IK in this cell line.

CONCLUSIONThe RVD process of intestine cell was dependent on the parallel activation of Cl- channel and K+ channel. The subtype of K+ channel in volved in the RVD process was IK channel.

Cell Line ; Cell Size ; drug effects ; Chloride Channels ; antagonists & inhibitors ; metabolism ; Epithelial Cells ; cytology ; Humans ; Hypotonic Solutions ; Intestine, Small ; cytology ; Potassium Channel Blockers ; pharmacology ; Potassium Channels ; metabolism ; Potassium Channels, Calcium-Activated ; metabolism

OBJECTIVETo investigate the expression of CLCA3 and Muc5ac in nasal mucosa in allergic rhinitis rats and the effects of glucocorticoid on its expression.

METHODSThirty SD rats were randomly divided into allergic rhinitis group, dexamethasone group and control group. Expression of CLCA3 mRNA and Muc5ac protein in nasal mucosa were detected by RT-PCR and immunohistochemical assay, respectively.

RESULTSCLCA3 mRNA and Muc5ac protein in allergic rhinitis group were significantly higher than those in control group (t = 8.565, 5.317, P < 0.01, respectively). The increased expression of CLCA3 mRNA in allergic rhinitis group was well correlated with the expression of Muc5ac protein and the correlation coefficient was 0.813 (P < 0.05). After treatment with dexamethasone, the expression of CLCA3 mRNA and Muc5ac protein was notably lower than that in allergic rhinitis group (t = 3.102, 2.226, P < 0.05, respectively).

CONCLUSIONSThe stronger gene expression of CLCA3 exists, complicated with mucus overproduction in the nasal mucosa of allergic rhinitis rats. CLCA3 expression may play a pivotal role in mucus overproduction in allergic rhinitis. Dexamethasone substantially downregulates the expression of CLCA3 mRNA and Muc5ac protein.

Animals ; Calcium Channel Agonists ; metabolism ; Chloride Channels ; metabolism ; Dexamethasone ; pharmacology ; Female ; Glucocorticoids ; pharmacology ; Mucin 5AC ; metabolism ; Nasal Mucosa ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic, Perennial ; metabolism

OBJECTIVETo investigate the expression of TMEM16A in gastric carcinoma and its clinical implications.

METHODSA total of 72 surgical specimens of gastric carcinoma were collected for examination of TMEM16A expression with immunohistochemical staining.

RESULTSTMEM16A expression was detected in the cytoplasm and cell membrane of the tumor cells. Of the 72 specimens of the tumor tissues, the total positivity rate of TMEM16A expression was 80.56% (58/72), significantly higher than the rate in the adjacent tissues (4.17%, 3/72, P<0.005).

CONCLUSIONAberrant expression of TMEM16A occurs in the majority of gastric carcinoma cases. TMEM16A can be used as a new candidate target for diagnosis and treatment of gastric carcinoma.

Adult ; Aged ; Anoctamin-1 ; Carcinoma ; metabolism ; pathology ; Chloride Channels ; metabolism ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Proteins ; metabolism ; Stomach Neoplasms ; metabolism ; pathology

OBJECTIVETo explore the effects of ANO1 overexpression on the proliferation, detachment, spreading, and migration of laryngocarcinoma Hep-2 cell line.

METHODSANO1-overexpressing Hep-2 cell line was selected as the assay group, and Hep-2 cell line with empty plasmid was selected as the control group. MTT assay was used to detect the proliferation abilities of Hep-2 cells in both two groups. Cell detachment assay and spreading assay were used to detect the detachment and spreading abilities of Hep-2 cells. Boyden chamber invasion assay, wound healing assay in vitro, and niflumic acid block chloride channel were used to detect the migration abilities of Hep-2 cells. All data were analyzed by SPSS 10.0 software package.

RESULTSCell proliferation assay by MTT showed that, compared with the control group, the optical density value of assay group was not significantly different (P=0.62). The results of cell detachment assay and cell spreading assay showed the cell detachment rates and cell spreading rates in assay group were significantly higher than those in control group (P<0.0001). The results of Boyden chamber invasion assay showed the percentages of cells migrating through the membrane in assay group were significantly higher than those in control group (P<0.0001). The results of in vitro wound healing experiments showed the wound area rate in assay group was significantly lower than that in control group (P<0.0001). The results of niflumic acid blocking chloride channel experiments showed the wound area rates in assay group were significantly higher than those in control group (P<0.0001).

CONCLUSIONANO1 overexpression does not remarkably alter the proliferation rate of cancer cells, but increases the migration, spreading, and detachment capacities of head and neck squamous cell carcinoma.

Anoctamin-1 ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Cycle ; Cell Line, Tumor ; Cell Movement ; Chloride Channels ; metabolism ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; Neoplasm Proteins ; metabolism

Chloride channels belong to a superfamily of ion channels that permit passive passage of anions, mainly chloride, across cell membrane. They play a variety of important physiological roles in regulation of cytosolic pH, cell volume homeostasis, organic solute transport, cell migration, cell proliferation, and differentiation. However, little is known about the functional regulation of these channels. In this study, we generated an integrated transgenic worm strain expressing green fluorescence protein (GFP) fused CLC-type chloride channel 1 (CLH-1::GFP), a voltage-gated chloride channel in Caenorhabditis elegans (C. elegans). CLH-1::GFP was expressed in some unidentified head neurons and posterior intestinal cells of C. elegans. Interacting proteins of CLH-1::GFP were purified by GFP-Trap, a novel system for efficient isolation of GFP fusion proteins and their interacting factors. Mass spectrometry (MS) analysis revealed that a total of 27 high probability interacting proteins were co-trapped with CLHp-1::GFP. Biochemical evidence showed that eukaryotic translation elongation factor 1 (EEF-1), one of these co-trapped proteins identified by MS, physically interacted with CLH-1, in consistent with GFP-Trap experiments. Further immunostaining data revealed that the protein level of CLH-1 was significantly increased upon co-expression with EEF-1. These results suggest that the combination of GFP-Trap purification with MS is an excellent tool to identify novel interacting proteins of voltage-gated chloride channels in C. elegans. Our data also show that EEF-1 is a regulator of voltage-gated chloride channel CLH-1.
Animals ; Animals, Genetically Modified ; Caenorhabditis elegans ; genetics ; metabolism ; Caenorhabditis elegans Proteins ; metabolism ; Chloride Channels ; metabolism ; Green Fluorescent Proteins ; chemistry ; Mass Spectrometry ; Peptide Elongation Factor 1 ; metabolism