Serotonin function in panic disorder: important, but why?
The essential role of serotonin (5-hydroxytryptamine (5-HT)) system in the neurobiology and pharmacotherapy of panic disorder (PD) continues to be a topic of intensive interdisciplinary research. Interest in the involvement of 5-HT in PD has been fuelled by clinical studies demonstrating that medications increasing the synaptic availability of 5-HT, such as selective 5-HT re-uptake inhibitors, are effective in the treatment of PD. Rival theories of 5-HT deficiency vs excess have attempted to explain the impact of 5-HT function in PD. In the past decade, knowledge of the role of 5-HT in the neurobiology of PD has expanded dramatically due to much new research including experimental, treatment, brain-imaging, and genetic studies. The current review attempts to summarize the new data and their implications. The challenge and treatment studies generally confirm the specific inhibitory influence of 5-HT on panicogenesis. The brain-imaging studies in PD patients demonstrate functional and clinically relevant alterations in various elements of 5-HT system affecting the neurocircuitry of panic. The findings of genetic association studies suggest that certain 5-HT-related genes may contribute to the susceptibility to PD; however, these data are rather limited and inconsistent. It appears that, even if not the primary etiological factor in PD, the 5-HT function conveys important vulnerability, as well as adaptive factors. A better understanding of these processes may be critical in achieving progress in the treatment of patients suffering from PD.
Maron
Eduard
E
Department of Psychiatry, University of Tartu, Tartu, Tartumaa, Estonia. eduard.maron@kliinikum.ee
Shlik
Jakov
J
D000818:Animals; D001921:Brain / Q000473:pathology; D006801:Humans; D008995:Monoamine Oxidase / Q000235:genetics; D016584:Panic Disorder / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D011985:Receptors, Serotonin / Q000235:genetics / Q000502:physiology; D012701:Serotonin / Q000235:genetics / Q000502:physiology*; D018490:Serotonin Agents / Q000627:therapeutic use; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics
D011985:Receptors, Serotonin; C493230:SLC6A4 protein, human; D018490:Serotonin Agents; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; D008995:Monoamine Oxidase