Figure 5

Figure 5

Carvedilol treatment might directly act on rods cells. To determine the extent to which carvedilol act directly on rods, we conducted a GloSensor cAMP assay with human Y79 cells. (a) Representative dose–response curves of GloSensor-transfected Y79 cells treated with half-log concentrations of isoproterenol (red trace; N = 4) or percentage-matched DMSO (black trace; N = 4). These plots were normalized to the maximum average luminescent level recorded per experiment. Error bars show ± 1 s.e.m. Isoproterenol was capable of increasing cAMP signaling through β-adrenergic receptor binding with an pEC50 of 7.49 ± 1.07. (b) Representative dose–response curves of GloSensor-transfected Y79 cells pretreated with half-log doses of carvedilol (blue trace; N = 4) or percentage-matched DMSO (red trace; N = 4). Cells were then challenged with a 10 μM isoproterenol that could induce maximal cAMP response, as shown in (a). Carvedilol pretreatment was capable of preventing isoproterenol-mediated cAMP increases with an pIC50 of 6.51 ± 0.67.