Abstract: Homeostasis of the central nervous system relies on the proper integration of cell‐signaling pathways recruited by a variety of neuronal and non‐neuronal factors, with the aim of tightly controlling neurotransmitter metabolism, storage, and transport. We took advantage of the 1C11 neuroectodermal cell line, endowed with the capacity to selectively differentiate into serotonergic (1C115–HT) or noradrenergic (1C11NE) neurons, to identify functional targets of serotonin (5‐hydroxytryptamine [5–HT]) and norepinephrine (NE) autoreceptors possibly involved in the control of neuronal functions. We demonstrate that 5‐HT2Band adreno α1Dreceptors are coupled to reactive oxygen species (ROS) production through NADPH oxidase activation in 1C115–HTand 1C11NEneuronal cells, respectively. In the signaling cascade linking 5–HT2Breceptors to NADPH oxidase, phospholipase A2‐mediated arachidonic acid production is required for ROS synthesis. ROS, in turn, act as second message signals and control the activation of TACE (TNF‐α converting enzyme), a member of a disintegrin and metalloproteinase family. 5–HT2Band α1Dreceptor stimulation triggers TACE‐dependent TNF‐α shedding in the surrounding milieu of 1C115–HTand 1C11NEcells. In these cells, shed TNF‐α triggers degradation of 5‐HT and NE into 5‐HIAA and MHPG, respectively. Finally, we observe that 5‐HT2Band α1Dreceptor couplings to the NADPH oxidase‐TACE cascade are strictly restricted to 1C11‐derived progenies that have implemented a complete neuronal phenotype. Altogether, our data indicate that couplings of 5‐HT2Band α1Dautoreceptors to ROS and TNF‐α signaling control neurotransmitter metabolism in 1C11‐derived neuronal cells. Eventually, we might explain the origin of oxidative stress and high level of TNF‐α in neurodegenerative diseases as a consequence of deviation of normal signaling pathways coupled to neurotransmitters.