Physiologie des humanen Hornhautendothels – neue Erkenntnisse durch elektrophysiologische Untersuchungen

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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