Figure 5.

Inhibition of hyperpolarization to ACh by CBX and βGA. Representative responses of V_m to ACh under control conditions and during exposure to GA derivatives. Treatment with each respective GA derivative was initiated 5 min prior to records shown. (A) Control recording of hyperpolarization to ACh. (B) Attenuated hyperpolarization to ACh during exposure to 30 µM CBX. (C) Inhibition of hyperpolarization to ACh during exposure to 100 µM CBX. (D) Summary data for effect of [CBX] on hyperpolarization to ACh (n= 7). *Significantly different from control (C), P < 0.05. (E) Control recording of hyperpolarization to ACh. (F) Attenuated hyperpolarization to ACh during 10 µM βGA. (G) Inhibition of hyperpolarization to ACh during spontaneous depolarization to 30 µM βGA. (H) Summary data for effect of [βGA] on hyperpolarization to ACh (n= 3). *Significantly different from control (C), P < 0.05. Note transient nature of hyperpolarization during periods of ACh stimulation in A, B, E and F.