Figure 5. Electroretinogram analysis of transgenic mice at various ages. A: Amplitudes of b-waves of PGK-Groenouw transgenic mice’s electroretinogram (ERG) distributed in function of their age. B: ERG recordings in response to single flashes in scotopic conditions. Two different six-month-old PGK-BIG Groenouw transgenic animals showed either a normal response (upper panel) or a flat ERG (lower panel). Conditions: A1 to V1 shows records with increasing intensities of light from 0.1 to 25000 mcds/m² and each division of the time axis correspond to 40 ms. U1 to j1 shows records with increasing frequencies of flashlight from 0.5 to 30 Hz and each division of the time axis correspond to 50 ms.