While the Deakin-Graeff hypothesis of serotonin function in anxiety disorders was appropriate to explain the data collected on the behavioral effects of serotonergic drugs microinjected in the amygdala or PAG, posterior analyses proved the reality to be far more nuanced than this hypothesis could cover. At the same time, while 5-HT1A agonists decrease anxiety- and fear-like behavior when microinjected in the basolateral amygdala and PAG, they increase anxiety-like behavior when microinjected in the septo-hippocampal system. Similarly, while 5-HT2 receptor agonists in the PAG reduce measures of fear and anxiety, they increase anxiety-like behavior when microinjected into the basolateral amygdala and septo-hippocampal system. Overall, these pharmacological results suggest that the regulation of anxiety-like behavior by serotonin is complex, with different receptors producing different results depending on the structure.
KeywordsAnxiety Disorder Dorsal Raphe Nucleus Basolateral Amygdala Receptor Editing Serotonergic Drug
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