FIGURE 4.

Inhibition of PLC/IP₃/Ca²⁺ signaling preserves retinal morphology in light-challenged Abca4^−/−Rdh8^−/− mice. A, 4- to 5-week-old Abca4^−/−Rdh8^−/− mice were exposed to white light at 10,000 lux for 30 min after pretreatment with either vehicle control (DMSO) or the PLC inhibitor, U-73122. In A: a, retinal histology (63×), with * indicating disorganized and reduced length of outer/inner segments, and b, analysis of ONL thickness were performed 7 days after illumination. B, light-challenged Abca4^−/−Rdh8^−/− mice were pretreated with either vehicle control (DMSO) or 2-APB, an antagonist against IP₃-mediated intracellular Ca²⁺ release. In B: a, retinal histology was analyzed 7 days after illumination; b, in situ ROS production after 2-APB treatment was assessed as described in Fig. 2.