Figure 1.

ISO, AziISO, SEVO, and AziSEVO α₁β₃γ_2L GABA_A receptor activity. A) Membrane view of the α₁β₃γ₂ GABA_A receptor homology model and schematic of the cross-section as indicated by the gray dashed line of the receptor transmembrane domain viewed from the synaptic cleft. Receptor is colored by subunit type (α₁, salmon; β₃, yellow; and γ₂, slate), and membrane-spanning helices (M1–M4) are labeled accordingly for each subunit. The plus and minus subunit interfaces are indicated for each subunit, and the pore (P) is indicated as a gray circle. B) Chemical structures of volatile anesthetics and their photolabel analogs. C) Representative traces of evoked current by GABA EC₁₀ control and after combined GABA EC₁₀ and 0.3 mM ISO, AziISO, SEVO, and AziSEVO exposures within individual X. laevis oocytes expressing the α₁β₃γ_2L GABA_A receptor. D) Fold potentiation of GABA EC₁₀ by 0.3 mM ISO, AziISO, SEVO, and AziSEVO within X. laevis oocytes expressing the α₁β₃γ_2L GABA_A receptor. Data were analyzed by Mann–Whitney U test that compared the evoked currents of the parent anesthetic with the corresponding photolabel analog. No significant differences were observed.