Blocking potassium channels that contain the Kv1.2 subunit triggers glutamate release in the rat prefrontal cortex, mimicking the effect of serotonin on thalamocortical terminals. The potassium channel blocker α-dendrotoxin (DTX), which selectively targets Kv1.1-, Kv1.2-, and Kv1.6-containing channels, induced excitatory postsynaptic currents (EPSCs) in layer V pyramidal neurons similar to those caused by serotonin acting on 5-HT2A receptors. Both DTX- and serotonin-induced EPSCs were blocked by tetrodotoxin and ω-agatoxin-IVA, suppressed by μ-opiates and thalamic lesions, and showed mutual occlusion, indicating a shared mechanism. This suggests that serotonin triggers glutamate release by inhibiting Kv1.2-containing potassium channels on thalamocortical terminals.
MDMA-assisted psychotherapy shows promise for PTSD, especially when standard treatments like SSRIs and trauma-focused cognitive behavioral therapy have failed. A review of evidence from human and rodent studies examines two main explanations for its effects: a neurobiological model, where MDMA reduces amygdala reactivity, boosts hippocampal connectivity, and alters serotonin and oxytocin signaling to aid fear extinction, memory reconsolidation, and neuroplasticity; and a relational model, where MDMA's prosocial and empathogenic qualities strengthen the therapeutic alliance and patient suggestibility. Rather than being mutually exclusive, these processes likely work together, with MDMA creating a "window of emotional safety" that enables both neurobiological and interpersonal healing. Understanding this dual action is key to refining treatment protocols and therapist training.