Ketamine exerts rapid antidepressant effects but is limited by dissociative and abuse-related side effects, highlighting the need for safer alternatives. Here, we identify 3C-DCK, a rationally designed ketamine derivative, through adenosine dynamics in the medial prefrontal cortex (mPFC). Using the GRABAdo1.0 sensor, we show that 3C-DCK elicits more potent and sustained extracellular adenosine release than ketamine at lower doses. Mechanistically, 3C-DCK lowers the intracellular ATP/ADP ratio, thereby driving equilibrative nucleoside transporter (ENT)-dependent adenosine efflux without inducing neuronal hyperexcitation or extracellular ATP hydrolysis. In chronically stressed mice, a single 2 mg/kg dose produced rapid and durable antidepressant-like effects lasting up to 72 h, exceeding the duration of ketamine. These effects required A1 and A2A receptor signalling and occurred without hyperlocomotion or ataxia. Together, our findings establish adenosine signaling as a druggable axis for dissociating therapeutic efficacy from ketamine-associated adverse effects and provide a framework for the development of next-generation rapid-acting antidepressants.
