Purpose: Fenamate sensitivity of the large-conductance K+ current in the corneal epithelium suggests that K+ transport could be modulated by arachidonic acid (AA) and/or its metabolites, which also regulate corneal epithelial migration. The main purpose of this study was to investigate AA-induced modulation of K+ currents expressed in the bovine corneal epithelium.
Methods: Freshly isolated bovine corneal epithelial cells were perfused with Ringer solution. Whole-cell currents were recorded by using either the conventional whole-cell-patch or the perforated-patch configuration.
Results: Two distinct types of K+ currents dominated the whole-cell current. The first was a voltage-gated K+ current that was inactivated completely by membrane depolarization. The inactivating voltage-gated K+ current was largest in presumptive basal cells. The second was a noisy, sustained K+ current that was never inactivated and seemed to be a counterpart of the large-conductance K+ current reported in the rabbit corneal epithelium. External application of AA (5-20 microm) inhibited the inactivating voltage-gated K+ current and augmented the noisy, sustained K+ current. Identical dual modulation was induced by other fatty acids (e.g., palmitoleic acid) that are not substrates for enzymes in the AA cascade.
Conclusions: An inactivating voltage-gated K+ channel was identified for the first time in the corneal epithelium. AA and some fatty acids may directly activate the large-conductance K+ channel to augment its housekeeping functions in corneal epithelial cells.
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Curr Eye Res
January 2025
Department of Ophthalmology, Medical University of Graz, Graz, Austria.
Purpose: To retrospectively describe the performance of topical insulin in persistent corneal epithelial defects (CED) and persistent corneal ulcers.
Methods: We reviewed cases of patients treated for persistent CED and persistent corneal ulcers using topical insulin in a concentration of 25 IU per milliliter three times per day. The closure rate of CED and corneal ulcers was the main outcome measure.
Viruses
January 2025
Department of Ophthalmology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou 450003, China.
COVID-19, caused by SARS-CoV-2, has presented formidable challenges to global health since its emergence in late 2019. While primarily known for respiratory symptoms, it can also affect the ocular surface. This review summarizes the effects of SARS-CoV-2 on ocular surface immunity and inflammation, focusing on infection mechanisms, immune responses, and clinical manifestations.
View Article and Find Full Text PDFJ Clin Med
January 2025
Ophthalmology Section, Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy.
To report the cosmetic, clinical, and visual outcomes of a combined surgical approach for treating a corneal/limbal dermoid using excision and a three-layered amniotic membrane graft with fibrin glue. An 18-year-old female presented with impaired vision and ocular discomfort caused by a prominent dome-shaped limbal congenital dermoid on the inferotemporal cornea, resulting in a significant aesthetic concern. A full assessment, including refraction, best-corrected visual acuity (BCVA), corneal topography, aberrometry and anterior segment OCT (AS-OCT) was conducted to plan the surgical approach.
View Article and Find Full Text PDFDiagnostics (Basel)
January 2025
Department of Ophthalmology, Faculty of Medicine, Selcuk University, Konya 42130, Türkiye.
In this study, we aim to evaluate in vivo confocal microscopy (IVCM) findings of corneal stromal dystrophies (CSDs) including granular, macular and lattice corneal dystrophy that can be used for differential diagnosis and monitoring recurrences after surgical interventions. : Patients diagnosed with CSD who were followed-up in the cornea and ocular surface unit were included in this study. IVCM was performed using the Heidelberg Retina Tomograph 3, Rostock Cornea Module (Heidelberg Engineering, Germany) and anterior segment optical coherence tomography (AS-OCT) imaging was performed using the Spectralis OCT (Heidelberg Engineering, Germany).
View Article and Find Full Text PDFSci Rep
January 2025
Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Corneal ulcer is one of the most important ophthalmic emergencies. A portable, recordable, and smartphone-attachable slit-lamp device called the "Smart Eye Camera" (SEC) is introduced to compare evaluating corneal ulcers between the SEC and the conventional slit-lamp. A total of 110 participants were included in the study, consisting of 55 patients with corneal ulcers and 55 age- and gender-matched healthy volunteers as controls.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!