Zusammenfassung
Die Identifizierung von apoptotischen oder geschädigten humanen Hornhautendothel(HCE)-Zellen
ist derzeit auf eine morphologische Beurteilung und Vitalfärbung begrenzt. Spezielle
elektrophysiologische Untersuchungen könnten künftig helfen, geschädigte HCE Zellen
bereits in einem früheren Stadium zu erkennen. Neben Calcium Imaging ist die sogenannte
Patch-Clamp-Technik eine wichtige Testmethode, mit der man die Wirkung verschiedenster
Substanzen auf Ionenkanäle und Rezeptoren der Zellmembran überprüfen kann. Erste elektrophysiologische
Pilotexperimente mit kultivierten und frisch isolierten HCE-Zellen haben vielversprechende
Ergebnisse hervorgebracht. So wurde erstmals die Expression bestimmter Transient-Rezeptor-Potenzial-
Kanäle (TRPs) in HCE-Zellen nachgewiesen. Die Funktion dieser TRP-Kanäle ist allerdings
noch nicht völlig geklärt. Beim Menschen spielen TRP-Kanäle eine wichtige Rolle bei
der Wahrnehmung von Geschmack, Pheromonen, Temperatur und Schmerz und sind an Osmolarität
beteiligt. Die Übersichtsarbeit fasst den Stand der Literatur zur Elektrophysiologie
des humanen Hornhautendothels zusammen und leitet daraus mögliche Ansätze zu einem
empfindlichen Vitalitäts- und Funktionstest unter Ausnutzung der elektrophysiologischen
Eigenschaften von HCE Zellen ab.
Abstract
Currently, the identification of apoptotic or damaged human corneal endothelial (HCE)
cells is limited to a morphological assessment and vital staining. Specific electrophysiological
investigations may prospectively help to identify damaged HCE cells at an earlier
stage. Besides calcium imaging, the so-called patch-clamp technique is an important
test method enabling one to assay the effect of various substances on ion channels
and receptors of the cell membrane. First electrophysiological pilot experiments with
cultivated and freshly isolated HCE cells have revealed promising results. In this
way, the expression of certain transient receptor potential channels (TRPs) could
be demonstrated. However, the function of these channels is still not fully elucidated.
In humans, TRPs play a crucial role in the sense of taste, pheromones, temperature
and pain and are involved in osmolarity. This review summarises the current literature
on the electrophysiology of the human corneal endothelium and deduces potential approaches
to a sensitive vitality and function test under utilisation of the electrophysiological
properties of HCE cells.
Schlüsselwörter
Hornhautendothel - In-vitro-Elektrophysiologie - Zellvitalität - Ionenkanäle
Key words
human corneal endothelium - in vitro electrophysiology - cell vitality - ion channels
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Stefan Mergler
Klinik für Augenheilkunde, Charité Universitätsmedizin Berlin
Augustenburger Platz 1
13353 Berlin
Phone: ++ 49/30/55 96 48
Fax: ++ 49/30/55 99 48
Email: stefan.mergler@charite.de
