Changes in membrane conductance play a pathogenic role in osmotic glial cell swelling in detached retinas.
Detachment of the neural retina from the pigment epithelium may be associated with tissue edema; however, the mechanisms of fluid accumulation are not understood. Because retinal detachment is usually not accompanied by vascular leakage, we investigated whether the osmotic swelling characteristics of retinal glial (Müller) cells are changed after experimental detachment of the porcine retina. Osmotic stress, induced by application of a hypotonic bath solution to retinal slices, caused swelling of Müller cell bodies in 7-day-detached retinas, but no swelling was inducible in slices of control retinas. Müller cell somata in slices of retinal areas that surround local detachment in situ also showed osmotic swelling, albeit at a smaller amplitude. The amplitude of osmotic Müller cell swelling correlated with the decrease in the K+ conductance, suggesting a causal relationship between both gliotic alterations. Further factors implicated in Müller cell swelling were inflammatory mediators and oxidative stress. We propose that a dysregulation of the ion and water transport through Müller cells may impair the fluid absorption from the retinal tissue, resulting in chronic fluid accumulation after detachment. This knowledge may lead to a better understanding of the mechanisms involved in retinal degeneration after detachment.
Wurm
Antje
A
Paul Flechsig Institute of Brain Research, Department of Ophthalmology and Eye Clinic, Faculty of Medicine, University of Leipzig, Liebigstrasse 10-14, D-04103 Leipzig, Germany.
Pannicke
Thomas
T
Iandiev
Ianors
I
Bühner
Eva
E
Pietsch
Uta-Carolin
UC
Reichenbach
Andreas
A
Wiedemann
Peter
P
Uhlmann
Susann
S
Bringmann
Andreas
A
D000818:Animals; D002462:Cell Membrane / Q000502:physiology*; D048429:Cell Size; D005260:Female; D007038:Hypotonic Solutions; D007150:Immunohistochemistry; D008297:Male; D009457:Neuroglia / Q000502:physiology*; D009995:Osmosis; D018384:Oxidative Stress; D024661:Potassium Channels, Inwardly Rectifying / Q000378:metabolism; D011687:Purines / Q000494:pharmacology; D012163:Retinal Detachment / Q000209:etiology / Q000378:metabolism*; D013552:Swine
D007038:Hypotonic Solutions; D024661:Potassium Channels, Inwardly Rectifying; D011687:Purines; C030985:purine