In this study, we probed for differences between GIRK2a and GIRK2c in an array of expression systems. Our findings suggest that these two isoforms differ primarily in terms of subcellular trafficking, with GIRK2c achieving a more uniform distribution throughout neurons, including distal dendrites. This difference in subcellular trafficking likely underlies the differing abilities of GIRK2a and GIRK2c to support slow IPSCs evoked via the electrical stimulation of proximal and distal dendritic fields. Indeed, our findings suggest that GIRK2c is critical for ensuring robust synaptic inhibitory GIRK-dependent responses in the distal dendritic fields of CA1 pyramidal neurons.
