Optogenetic stimulation of medial prefrontal cortex Drd1 neurons produces rapid and long-lasting antidepressant effects.

Impaired function in the medial prefrontal cortex (mPFC) contributes to depression, and the therapeutic response produced by novel rapid-acting antidepressants such as ketamine are mediated by mPFC activity. The mPFC contains multiple types of pyramidal cells, but it is unclear whether a particular subtype mediates the rapid antidepressant actions of ketamine. Here we tested two major subtypes, Drd1 and Drd2 dopamine receptor expressing pyramidal neurons and found that activating Drd1 expressing pyramidal cells in the mPFC produces rapid and long-lasting antidepressant and anxiolytic responses. In contrast, photostimulation of Drd2 expressing pyramidal cells was ineffective across anxiety-like and depression-like measures. Disruption of Drd1 activity also blocked the rapid antidepressant effects of ketamine. Finally, we demonstrate that stimulation of mPFC Drd1 terminals in the BLA recapitulates the antidepressant effects of somatic stimulation. These findings aid in understanding the cellular target neurons in the mPFC and the downstream circuitry involved in rapid antidepressant responses.