ArticleInvestigative ophthalmology & visual science2009
In situ fluorescence measurement of tear film [Na+], [K+], [Cl-], and pH in mice shows marked hypertonicity in aquaporin-5 deficiency.
Article in Investigative ophthalmology & visual science, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 29 papers.
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Who cites it
29 citing papers in PubMed, 43 citations in OpenAlex.
- Measurement of Anions in Dog Tear Fluid Using Ion Chromatography.Veterinary ophthalmology · 2026Article
- Model of ocular surface ion and water transport predicts efficacy of dry eye therapeutics.The Journal of general physiology · 2026Article
- Age-related lncRNA alterations of SDHAP2_miR-17-5p/miR-20b-5p_RAB11FIP1 ceRNA network in donor-derived human limbal epithelial cells.Frontiers in cell and developmental biology · 2026Article
- Mechanisms of acupuncture in the treatment of dry eye disease: narrative review of experimental studies.International ophthalmology · 2025Review
- Non-contact confocal calcium imaging ofBiomedical optics express · 2025Article
- Development and validation of a method to generate phenol red thread tests.The ocular surface · 2024Article
- Elucidating the roles of electrolytes and hydrogen bonding in the dewetting dynamics of the tear film.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Luminescence Probes in Bio-Applications: From Principle to Practice.Biosensors · 2024Review
- Aquaporins in the Cornea.International journal of molecular sciences · 2024Review
- Ion channels in dry eye disease.Indian journal of ophthalmology · 2023Review
- Aquaporins in Glandular Secretion.Advances in experimental medicine and biology · 2023Article
- Ocular Surface Ion Transport and Dry Eye Disease.Current ophthalmology reports · 2022Article
- Fluorescence Sensing Technologies for Ophthalmic Diagnosis.ACS sensors · 2022Review
- Topical administration of ambroxol eye drops augments tear secretion in rabbits.Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie · 2021Article
- Review
- Sodium-Sensitive Contact Lens for Diagnostics of Ocular Pathologies.Sensors and actuators. B, Chemical · 2021Article
- Native fluorescence of tear fluid as a tool for diagnostics of glaucoma.RSC advances · 2021Article
- Experimental Pharmacotherapy for Dry Eye Disease: A Review.Journal of experimental pharmacology · 2021Review
- Effects of Topical Gabapentin on Ocular Pain and Tear Secretion.Frontiers in pharmacology · 2021Article
- Ions, the Movement of Water and the Apoptotic Volume Decrease.Frontiers in cell and developmental biology · 2020Review
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
Abstract
purposeTear film composition depends on water and ion transport across ocular surface epithelia and on fluid secretion by lacrimal glands. The purpose of this study was to establish in situ fluorescence methods to measure tear film ionic concentrations and pH in mice and to determine whether tear film composition is sensitive to deficiency of the major ocular surface aquaporin water channels.
methodsTear film ionic concentrations and pH were measured in anesthetized mice by ratio imaging fluorescence microscopy after topical application of ion/pH-sensing, dual-wavelength fluorescent indicators. [Na(+)], [K(+)], and [Cl(-)] were measured with membrane-impermeant indicators developed by our laboratory, and pH was measured with bis(carboxyethyl)-carboxyfluorescein fluorescence-conjugated dextran. Measurements were performed on wild-type mice and on knockout mice lacking aquaporins AQP1, AQP3, and AQP5.
resultsIn wild-type mice, tear film [Na(+)] was 139 +/- 8 mM, [K(+)] was 48 +/- 1 mM, [Cl(-)] was 127 +/- 4 mM, and pH was 7.59 +/- 0.2 (SE; n = 5-8). pH did not differ significantly in the AQP knockout mice. [Na(+)] was increased by approximately twofold in AQP5 null mice (230 +/- 20 mM) and was greatly reduced after exposure of the ocular surface to a humidified atmosphere. [K(+)] was mildly reduced in AQP1 null mice.
conclusionsThese results establish an in situ optical methodology to measure tear film [Na(+)], [K(+)], [Cl(-)], and pH in living mice, without the need for fluid sampling. Tear film hypertonicity in AQP5 deficiency is likely caused by reduced transcorneal water secretion in response to evaporative water loss.
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