GIRK subunit expression in the dorsal horn of the spinal cord. Spinal cord sections from wild-type (A, B), GIRK1 knock-out (C, D), GIRK2 knock-out (E, F), and GIRK3 knock-out (G, H) mice were stained with anti-GIRK1 (left column) or anti-GIRK2 (right column) antibodies (Ab). Note the absence of GIRK1 and GIRK2 staining in sections from the corresponding knock-out mice (C, F, respectively) and their dramatic reduction in sections from GIRK2 knock-out (E) and GIRK1 knock-out (D) mice, respectively. Also note the slightly lower levels of GIRK1 in sections from GIRK3 knock-out (G), but not GIRK2 knock-out (H), mice. Results are representative of the data obtained from three complete sets of wild-type and GIRK knock-out mice.