Figure 5.

D1R activity does not affect rod bipolar cell sensitivity in the absence of serial inhibition. A–C, ERG b-wave responses of dark-adapted WT mice are plotted as a function of flash intensity and fit using a double hyperbolic function (Eq. 1). Experiments were conducted with either untreated mice or following intravitreal injections with D1R antagonist SKF83566, D1R agonist SKF81297, GABA_AR antagonist gabazine, or a combination of gabazine with either D1R drug. Specific pharmacological interventions used in each experiment are indicated and color-coded in the panels. D, Rod bipolar cell sensitivity in the presence of either gabazine alone or a combination of gabazine with D1R antagonist SKF83566 or D1R agonist SKF81297 was normalized to the dark sensitivity in the presence of gabazine alone and plotted as a function of background light. Between 3 and 10 eyes were analyzed for each condition; data are presented as mean ± SEM.