Emotional Roles of Mono-Aminergic Neurotransmitters in Major Depressive Disorder and Anxiety Disorders

Abstract

A growing body of researches support a role for dysfunction of serotoninergic, noradrenergic, and dopaminergic systems in the neurobiological processes involved in major depression disorder (MDD) and anxiety disorders (ADs). The physiological changes underlying abnormal signaling of 5-HT, NE, and DA may be due to either reduced presynaptic release of these neurotransmitters or aberrant signal transductions, and thus contributing to the alterations in regulation or function of receptors and/or impaired intracellular signal processing. Animal models demonstrate crucial responsiveness to disturbance of 5-HT, NE, and DA neurotransmissions. Postmortem and biochemical studies have shown altered concentrations of 5-HT, NE, and DA metabolites in brain regions that contribute importantly to regulation of mood and motivation in patients with MDD or ADs. Neuroimaging studies have found abnormal 5-HT, NE, and DA receptors binding and regulation in regard to receptor numbers. Medications that act on 5-HT, NE, and DA neurons or receptors, such as SSRIs and SNRIs, show efficacy in both MDD and ADs. The overlapping treatment response presumably suggests a common mechanism underlying the interaction of these disorders. In this paper, we reviewed studies from multiple disciplines to interpret the role of altered 5-HT, NE and DA mono-amine neurotransmitter functions in both MDD and ADs.

Epstein-Barr Virus dUTPase Induces Neuroinflammatory Mediators: Implications for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

“…58 The dopaminergic and serotonergic neurotransmitter systems are reported to play a critical role in the regulation of emotion and mood, and they have been implicated in a spectrum of neuropsychiatric disorders. 59,60 EBV replicates primarily in the tonsils/ nasopharynx and sheds in the saliva. 61 A number of reports have found that physical and/or psychosocial stress induces the reactivation of latent EBV.…”

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“…Lower concentrations of NE and serotonin (5-HT) in the brain [18][19][20][23][24][25] along with the effectiveness of antidepressant drugs 21,22 support the monoaminergic hypothesis of depression. Here, SI reduced NE in the OB and the dorsal hippocampus (dHIP), and 5-HT in the dHIP.…”

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“…Neurochemical unbalance may also be present in humans 18,19 and rodents 21,[35][36][37] under a depressive state. Particularly serotonin (5-HT) and NE levels may be disturbed in those situations 18,20,36 .…”