Figure 5. Effects of extended light exposure on dark adaptation of M‐cones in 2‐month‐old RDH8‐ and/or ABCA4‐deficient mice .

A, change of photopic ERG b‐wave S _f in vivo following illumination with green 530 nm Ganzfeld background light (300 cd m⁻², 15 min), and its subsequent recovery in the dark after bleaching the bulk of the remaining cone pigment (B) in control (n = 5), Abca4^−/−Gnat1^−/− (n = 6), Rdh8^−/−Gnat1^−/− (n = 6) and TKO (n = 5) mice. S _f was normalized to the corresponding dark‐adapted value (S _f ^DA) in each case. Initial rates of S _f recovery were determined from linear fits (shown in A) that yielded the following slopes: 0.36 min⁻¹ (control), 0.17 min⁻¹ (Abca4^−/−Gnat1^−/−), 0.17 min⁻¹ (Rdh8^−/−Gnat1^−/−) and 0.17 min⁻¹ (TKO). Bleaching was induced by a 30 s illumination with 520 nm LED light at time 0. The time course of light exposure is shown at the bottom. Error bars represent SEMs (smaller than symbol size for most data points).