Fig. 5.

Glial cell Ca²⁺ increases. (a) Intracellular glial Ca²⁺ increases evoked by photolysis of caged Ca²⁺. Photolysis evokes Ca²⁺ increases proportional to the duration of the photolysis flash. Numbers indicate flash duration for each trial. (b, c) Glial Ca²⁺ increases and a propagated Ca²⁺ wave evoked by photolysis of caged ATP. (b) A confocal image of the retina showing OGB-labeled glial cells. Asterisk indicates the site of caged ATP photolysis; scale bar, 50 μm. (c) Stimulation of glial cells by photolysis of caged ATP in the vitreous humor evokes Ca²⁺ increases in the stimulated cells and initiates a propagated Ca²⁺ wave. Ca²⁺ is measured in the three regions indicated in (b).