Insight into B5-I spinal interneurons and their role in the inhibition of itch and pain.

Abstract

The last few years have seen major advances in our understanding of spinal microcircuits that integrate somatosensory input, resulting in part from availability of mice that allow genetically defined neuronal populations to be marked or manipulated. However, a genetically defined population does not necessarily correspond to a functional population, and defining functional populations remains a major challenge. Here we begin to address this by focusing on a group of inhibitory interneurons in superficial dorsal horn. These have been variously identified as PrP-GFP,4,9 B5-I,6,7 or Dyn-cre2 neurons. However, it now appears that they represent largely overlapping populations stemming from a common lineage. Here, we summarize what is known about these neurons, and consider their roles in the inhibition of itch and pain.