Figure 5.

Determination of rhodopsin lifetime by fitting the model utilizing equation (17) to the activation phase of population averaged response families recorded with LERG-OS with 2-fold increments in flash strengths. (a,c,e) Presents the fitting outcome with different τ_R values to WT, GCAPs^−/−, and DKO response families, respectively. Black curves show the optimal amplification constants with different τ_R values and red curves show the sum of squared errors of the fits. The optimal τ_R values are found from the minima of the red curves. (b,d,f) Show the WT, GCAPs^−/−, and DKO response families, respectively, and the model fittings with the optimal τ_R and A values. (b) Response families from 10 WT experiments with flash strengths ranging from 1.7 to 187 R*rod⁻¹. The optimal τ_R was 51 ms and the subsequent amplification constant was 13.0 s⁻². (d) Response families from 6 GCAPs^−/− experiments with flash strengths ranging from 1.4 to 87 R*rod⁻¹. The optimal τ_R was 49 ms and the amplification constant was 15.7 s⁻². (f) Response families from 18 DKO experiments with flash strengths ranging from 1.4 to 170 R*rod⁻¹. τ_R of 28 ms and amplification constant of 18.9 s⁻² gave the optimal fit to the responses. With all mouse strains, the fitting was performed for responses ranging from dim flashes to the first saturated response.