Data from: Oxytocin and dopamine receptor expression: Cellular level implications for pair bonding

Oxytocin (Oxtr) and dopamine (Drd1, Drd2) receptors provide a canonical
example for how differences in neuromodulatory receptors drive individual
and species-level behavioral variation. These systems exhibit striking and
functionally-relevant differences in nucleus accumbens (NAc) expression
across monogamous prairie voles (Microtus ochrogaster) and promiscuous
meadow voles (Microtus pennsylvanicus). However, their cellular
organization remains largely unknown. Using multiplex in situ
hybridization, we mapped Oxtr, Drd1, and Drd2 expression in sexually naïve
and mate-paired prairie and meadow voles. Prairie voles have more Oxtr+
cells than meadow voles, but Oxtr distribution across dopamine-receptor
cell class was similar, indicating a general upregulation rather than cell
class bias. Oxtr was enriched in cells that express both dopamine
receptors (Drd1+/Drd2+) in prairie voles, suggesting these cells may be
particularly sensitive to oxytocin. We found no species or pairing-induced
differences in Drd1+ or Drd2+ cell counts, suggesting prior reports of
expression differences may reflect upregulation in cells already
expressing these receptors. Finally, we used single-nucleus sequencing to
provide the first comprehensive map of Oxtr and Drd1-5 across
molecularly-defined NAc cell types in the prairie vole. These results
provide a critical framework for understanding how nonapeptide and
catecholamine systems may recruit distinct NAc cell types to shape social
behavior.