Figure 3.

Subcellular distribution of GIRK1-IR in somata and dendrites in the CA1 region of hippocampus. (A) GIRK1–immunogold labeling (arrows) in a pyramidal cell soma is localized to the Golgi apparatus (G), small vesicular structures, and, less frequently, the plasma membrane (arrowhead). A gold particle is present in the nucleus (N), but this labeling was nonspecific. (B) In superficial str. radiatum, two dendritic shafts (D1 and D2) contain GIRK1–immunogold labeling (arrows). This labeling is associated primarily with the plasma membrane and to a lesser extent with intracellular organelles. Dendrite D1 possesses a thin, unlabeled simple spine (S) and receives a symmetric synapse on the shaft (curved arrow) from an unlabeled terminal (uT). (C) Dendrites in str. lacunosum-moleculare contain GIRK1–immunogold labeling (arrows) associated with the plasma membrane, intracellular vesicles, and a postsynaptic density (curved arrow). (Bar = 0.5 μm.)