Role of transmembrane chloride transporters in the fluid secretion of lacrimal gland duct cells

AbstractElectrophysiologic studies have characterized ion channels in lacrimal gland acinar cells, but due to relative paucity and inaccessibility, such studies on lacrimal gland duct cells are challenging. The duct cells are believed to secrete the high level of K+ that is present in tears. The goal of this project was to develop a method for isolation of viable, single duct cells, demonstrate their utility for patch-clamp recording and characterize the K+ channels expressed by duct cells. Exorbital lacrimal gland slices from Sprague-Dawley rats were incubated with collagenase. Under a microscope, the ducts were microdissected from the glands and then incubated with elastase and collagenase. Dispersed duct cells were plated on a cover slip coated with BD Cell-Tak. Duct cells were distinguished from acinar cells by their smaller size and lack of granularity. Whole-cell K+ currents were recorded from duct cells using the perforated-patch technique and pipettes with resistances of less than 10 MΩ. EGTA and CaCl2 in the pipette solution were adjusted to give 1 uM free Ca++. When held at −80 mV, duct cells showed K+ currents that activated at command voltages near 0 mV and reached amplitudes near 1 nA at +100 mV. Currents reached peak amplitude less than 20 ms after depolarization and did not inactivate. These currents were inactivated by holding the cells at 0 mV. Currents were blocked reversibly by TEA in the presence of Ca2+, but were not blocked by TEA in the absence of Ca2+. Currents were not affected by clotrimazole (10 uM) or Ba2+ (5 mM). A method has been established for isolation and dissociation lacrimal gland duct cells for electrophysiologic studies. These cells express a voltage-activated K+ channel that is dependent on the presence of intracellular Ca2+ and may correspond to the IKCa1 channel expressed on the apical membranes of lacrimal gland ducts.

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Gene Expression in Rat Lacrimal Gland Duct Cells Collected Using Laser Capture Microdissection: Evidence for K+Secretion by Duct Cells

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.05-0363 ◽

2006 ◽

Vol 47 (5) ◽

pp. 1876 ◽

Cited By ~ 30

Author(s):

John L. Ubels ◽

Holly M. Hoffman ◽

Sujata Srikanth ◽

James H. Resau ◽

Craig P. Webb

Keyword(s):

Gene Expression ◽

Lacrimal Gland ◽

Laser Capture Microdissection ◽

Duct Cells ◽

K Secretion ◽

Gland Duct ◽

Laser Capture

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Expression of IL-25, IL-33, and Thymic Stromal Lymphopoietin in Nasal Polyp Gland Duct Epithelium in Patients With Chronic Rhinosinusitis

American Journal of Rhinology and Allergy ◽

10.1177/1945892419835333 ◽

2019 ◽

Vol 33 (4) ◽

pp. 378-387 ◽

Cited By ~ 3

Author(s):

Yoshiyuki Nagata ◽

Shuichiro Maruoka ◽

Yasuhiro Gon ◽

Kenji Mizumura ◽

Hiroyuki Kishi ◽

...

Keyword(s):

Chronic Rhinosinusitis ◽

Nasal Mucosa ◽

Nasal Polyp ◽

Cytokine Expression ◽

Thymic Stromal Lymphopoietin ◽

Eosinophilic Infiltration ◽

Duct Cells ◽

Eosinophilic Chronic Rhinosinusitis ◽

Gland Duct

Background Nasal polyps accompany eosinophilic chronic rhinosinusitis (ECRS). Cytokines, including interleukin (IL)-25, IL-33, and thymic stromal lymphopoietin (TSLP) expressed in nasal mucosa have been implicated in polyp pathogenesis. We investigated the role of nasal polyp epithelium cytokine expression in eosinophilic infiltration in ECRS. Methods Tissues were collected from 39 patients undergoing nasal surgery. Cases were divided into 3 groups: control (CTR), non-ECRS (nECRS), and ECRS and were evaluated for IL-25, IL-33, and TSLP expression. Results Abundant eosinophilia was observed underneath the nasal mucosa and around the nasal ducts in polyps in ECRS and correlated positively with IL-33 protein expression. Conclusion Cytokine expression in nasal duct cells and eosinophilic infiltration around duct cells similar to those in the nasal mucosa occurred in the nasal epithelium of polyps, suggesting its role in inducing eosinophilic inflammation.

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Novel Insight Into the Role of CFTR in Lacrimal Gland Duct Function in Mice

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.17-22533 ◽

2018 ◽

Vol 59 (1) ◽

pp. 54 ◽

Cited By ~ 6

Author(s):

Orsolya Berczeli ◽

Eszter Vizvári ◽

Máté Katona ◽

Dénes Török ◽

László Szalay ◽

...

Keyword(s):

Lacrimal Gland ◽

Gland Duct ◽

Insight Into

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Characterization of Na+-K+-2Cl−Cotransporter Activity in Rabbit Lacrimal Gland Duct Cells

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.15-18462 ◽

2016 ◽

Vol 57 (8) ◽

pp. 3828 ◽

Cited By ~ 5

Author(s):

Eszter Vizvári ◽

Máté Katona ◽

Péter Orvos ◽

Orsolya Berczeli ◽

Andrea Facskó ◽

...

Keyword(s):

Lacrimal Gland ◽

Duct Cells ◽

Gland Duct

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Secretion of saliva by the rabbit mandibular gland in vitro : the role of anions

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1981.0181 ◽

1981 ◽

Vol 296 (1080) ◽

pp. 179-192 ◽

Cited By ~ 3

Keyword(s):

Mandibular Gland ◽

Fluid Secretion ◽

Salivary Secretion ◽

Suitable Alternative ◽

Secretory Rate ◽

Complete Replacement ◽

Primary Fluid ◽

Gland Duct

Salivary glands form their secretions by first elaborating an isotonic plasma-like primary fluid in the endpieces and then modifying the composition of this secretion during its passage along the gland duct system. We have studied the role of extracellular anions in both primary secretion and ductal modification with a recently developed technique for isolation and perfusion of the rabbit mandibular gland. Neither of the major extracellular anions (Cl - or HCO - 3 ) is essential for primary fluid secretion. HCO - 3 can be removed altogether and replaced with Cl - without diminution in secretory rate, provided that extracellular pH is maintained at 7.4, and its replacement with acetate actually enhances secretion. Complete replacement of Cl - with Br - also enhances secretion and replacement with I - , NO - 3 , CH 3 SO 4 or isethionate supports secretion but at progressively diminishing rates. Our data do not yet allow us to distinguish between an electroneutral Na + -Cl - cotransport model or a double countertransport (Na + -H + plus Cl - -HCO - 3 ) model as the basis of primary salivary secretion, or to propose any more suitable alternative model. With respect to ductal modification of the primary saliva, HCO - 3 omission inhibits ductal Na + absorption (i.e. salivary Na + concentration rises). This inhibition is probably related to an effect of pH on the postulated Na + -H + exchange mechanism in the luminal duct membrane since it can also be induced by lowering perfusate pH, and reversed by substitution of perfusate HCO - 3 with acetate (which enters saliva) but not HEPES (which does not enter the saliva). Substitution of perfusate Cl - with other anions seems not to inhibit ductal Na+ and K + transport markedly.

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