Calcium responses mediated by type 2 IP3-receptors are required for osmotic volume regulation of retinal glial cells in mice

NEUROSCIENCE LETTERS

卷:457

Article

Lipp, Stephan³  Wurm, Antje³  Pannicke, Thomas³  Wiedemann, Peter^1,2  Reichenbach, Andreas³  Chen, Ju⁴  Bringmann, Andreas^1,2 

[1] Univ Leipzig, Dept Ophthalmol, D-04103 Leipzig, Germany

[2] Univ Leipzig, Hosp Eye, D-04103 Leipzig, Germany

[3] Univ Leipzig, Paul Flechsig Inst Brain Res, D-04109 Leipzig, Germany

[4] Univ Calif San Diego, Dept Med, La Jolla, CA 92093 USA

关键词: Osmotic swelling;    Glial cell;    Retina;    IP(3)R2;    ATP;   

DOI  :  10.1016/j.neulet.2009.04.001

来源: Elsevier

【 摘 要 】

Prevention of osmotic swelling of retinal glial (Muller) cells is required to avoid detrimental decreases in the extracellular space volume during intense neuronal activity. Here, we show that glial cells in slices of the wildtype mouse retina maintain the volume of their somata constant up to similar to 4 min of perfusion with a hypoosmolar solution. However, calcium chelation with BAPTA/AM induced a rapid swelling of glial cell bodies. In glial cells of retinas from inositol-1,4,5-trisphosphate-receptor type 2-deficient (IP(3)R2(-/-)) mice, hypotonic conditions caused swelling of the cell bodies without delay. Exogenous ATP (acting at P2Y(1) receptors) prevented the swelling of glial cells in retinal slices from wildtype but not from IP(3)R2(-/-) mice. Muller cells from IP(3)R2(-/-) mice displayed a strongly reduced amplitude of the ATP-evoked calcium responses as compared to cells from wildtype mice. It is concluded that endogenous calcium signaling mediated by IP(3)R2 is required for the osmotic volume regulation of retinal glial cells. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

【 授权许可】

Free