Fig. 2

Effect of brimonidine and betaxolol on the oscillation frequency of local field potentials in rd10 retinas. The upper graphs show the analysis of the oscillation frequencies [Hz] during the individual perfusion steps with Ames’ medium (A.1^st–A.3^rd, white) and (a) 150 µM brimonidine (Br.1^st–Br.2^nd, light green) or (b) 100 µM betaxolol (Bx.1^st–Bx.2^nd, light blue). (247–277 channels analyzed for 150 µM brimonidine; 243 channels analyzed for 100 µM betaxolol). The lower graphs show the number of active channels with oscillations [%] during perfusion with Ames’ medium and 150 µM brimonidine or 100 µM betaxolol. Data are presented as box-and-whisker plots (not significant, 52–59 channels included for 150 µM brimonidine, 32–56 channels included for 100 µM betaxolol). The mean values of the oscillation frequency and the percentage recording channels with oscillations during the first Ames’ perfusion from all experiments are shown as dotted lines. The panels show representative recordings of four selected MEA channels during alternating perfusion with Ames’ medium and (a) 150 µM brimonidine or (b) 100 µM betaxolol. The 50 Hz low-pass filtered data illustrate the persistence of oscillations during brimonidine wash-in and the repeated disappearance of oscillations during betaxolol wash-in (x-axis scale: 500 ms, y-axis scale: ± 100 µV).