Figure 6. Curves represent the dose-responses of nAChR currents activated by ACh in the presence () or absence () of 4 μM bilirubin.

All nAChR currents evoked by ACh in SCG neurons were normalized to that induced by 100 μM ACh alone (referred to as Relative IACh). Administration of 4 μM bilirubin shifted the dose-responses of nAChR currents to the right, and markedly increased the potency and maximum efficacy of ACh (400 and 800 µM)-induced response. All data points are expressed as means ± SEMs (n = 3).