Fig. 2.

GABA produces membrane depolarization in β-cells. Representative traces show GABA-evoked currents (I_GABA, A) and GABA-induced depolarization (intracellular sharp recordings) (B) in INS-1 cells. (C) Current-clamp recording (at membrane potential of −60 mV) of INS-1 cells in the presence of GABA (100 μM) with or without Bic (100 μM). Intracellular Ca²⁺ measurements in INS-1 cells (D) and isolated islet β-cells (E) in the presence of GABA or GABA_AR agonist muscimol (10 μM) (E) with or without Bic. (*P < 0.05 and **P < 0.01; n = 3–5.)