Figure 4. Osmotic swelling properties of Müller cells from A₁AR^−/− and wildtype (Wt) mice. The cross-sectional area of Müller cell somata was measured after a 4 min perfusion of retinal slices with a hypoosmolar solution (in the absence of barium), and are expressed in percent of the soma size measured before hypotonic challenge (100%). A: Hypoosmotic exposure evoked swelling of Müller cell bodies in retinal slices from A₁AR^−/− mice. This was observed in freshly isolated retinas and retinal organ cultures. In contrast, in tissues from wild-type animals, swelling was induced in retinal organ cultures but not in freshly isolated retinas. B: Müller cells in retinal slices derived from A₁AR^−/− mice displayed a swelling of their cell bodies under hypoosmotic conditions (control). In slices of these mice, 10 µM adenosine did not prevent the swelling of the cells. The swelling was diminished in the presence of a cAMP-enhancing cocktail containing 100 µM pCPT-cAMP, 10 µM forskolin, and 100 µM IBMX. Significant differences versus freshly isolated cells from wild-type mice (the asterisk indicates a p<0.001). Significant swelling-inhibitory effect (the filled circle indicates a p<0.001).