OLM cells expressing Chrna2 exhibit differential innervation patterns along the dorsoventral axis of the hippocampus

Differences along the dorsal and ventral axis of the hippocampus reveal distinct processing characteristics, yet the connectivity patterns of different types of interneurons across hippocampal regions are not well understood. One specific group of interneurons, identified by the Chrna2 gene, known as OLMα2 cells, are noteworthy for their unique properties. These cells have a gate-switching function that regulates memory processes and risk-taking behavior differently across the dorsoventral axis. Using monosynaptic rabies tracing, we investigated how OLMα2 cells are wired in the dorsal, intermediate, and ventral hippocampus. We found differences in both intrinsic and extrinsic connectivity, shedding more light on the involvement of OLMα2 cells in regulating memory recall and consolidation via cholinergic mechanisms.