FIGURE 9.

Lack of an effect by physiological concentrations of ethanol. Non-concatenated α₄β₂δ (0.5:0.5:2.5 and 2.5:0.5:2.5), concatenated β₂-α₄-δ-α₄-β₂ (P1), and δ-β₂-α₄-β₂-α₄ (P5) receptors were expressed in Xenopus oocytes. The receptors were activated by a concentration of GABA eliciting EC₁₀ in the presence of 1 μm THDOC, followed by application of the same concentration of GABA/THDOC subsequently in combination with 0.1, 0.3, 1, 3, 10, and 30 mm ethanol. The relative current amplitude of the responses in the presence of ethanol compared with GABA/THDOC alone is given. Neither currents mediated by the non-concatenated α₄β₂δ or concatenated receptors were significantly modulated by ethanol in the concentration range of 0.1–30 mm. Data are expressed as mean ± S.E. n, number of oocytes.