Fig. 7.

Indistinguishable photoresponses of WT and S100B KO rods under conditions designed to raise intracellular Ca²⁺. (A) Averaged responses of the WT rod photoreceptor (upper panel) and a S100B KO rod photoreceptor (lower panel) to flashes of: 6, 13, 27, 51, 199, 827 and 3232 photons µm^-2 for both rods. Maximal response amplitudes were 2.6 and 3 pA, respectively. Flash monitor is shown as the bottom trace. (B) Stimulus-response relations for the rods from A, WT (black symbols) and S100B KO (gray symbols); some saturated-response points were omitted from each rod for illustrative purposes. i_0.5 was 12 and 14 photons µm^-2 for the WT and S100B KO, respectively. (C) Pepperberg plot for WT (black symbols) and S100B KO (gray symbols) rods. Values for τ_c, given from linear regression (continuous lines), were 194 ms for the 6 WT and 180 ms for 3 S100B KO. The Pearson product moment correlation coefficients for the WT and S100B KO rods were 0.84 and 0.88, respectively.