Fig. 6. Structure of GIRK-IRK chimeric subunits and effects of volatile anesthetics. The sequences of GIRK2 and IRK1 subunits are shown by filled and open columns, respectively. The putative transmembrane (M1 and M2) and pore-forming (P) domains are indicated by dotted lines. Interfaces between filled and open columns indicate chimera junction sites. The numbers in the right represent the percentage inhibition by 0.5 mm halothane and 1.6 mm F3 of current responses to a high-potassium solution. Values are mean ± SD of measurement of three to five oocytes. Current responses (μA) obtained were 4.4–12 for GIRK2, 6.2–9.8 for IRK1, 9.5–13 for GIRK2-087-IRK1, 1.3–7.9 for GIRK2-223-IRK1, and 1.5–7.2 for IRK1-061-GIRK2 channels. *Coexpressed with GIRK1 subunits. NC = no measurable current.