The Role of Dopamine as an Antidepressant Medication

Continues for 3 more pages »
Read full document

The Role of Dopamine as an Antidepressant Medication

By | April 2008
Page 1 of 4
The neural circuitry that controls mood under normal and abnormal conditions remains incompletely understood. Depression is the most common of the affective disorders and is linked worldwide to disability and premature death (Rang H.P., Dale M.M., Ritter J.M., & Moore P.K, 2003). Over the past four decades, inhibitors of biogenic amine reuptake have been the main drug therapy for the treatment of major depression, specifically 5-hydroxytryptamine (serotonin) reuptake inhibitors (SSRIs), serotonin/norepinephrine reuptake inhibitors (SNRIs) and tricyclic antidepressants. The purpose of this essay is to hypothesis as to why there are not more antidepressant drugs that directly affect dopamine in the brain. A possible reason is the findings that though dopamine is shown to have a role in the mesolimbic pathway, the role of dopamine in neurotransmission and the effect of manipulation of levels through antidepressants are still largely unknown. The limited focus on dopamine could also have been a result of the extensive evidence that the more commonly used antidepressants (such as SSRIs, SNRIs, and tricyclics ) work very well, as well as the lack of success achieved with use of available dopamine-enhancing medications. Finally, post-mortem studies of the dopaminergic neurotransmission system in depressed patients show inconclusive findings which do not support the hypothesis that depression will be decreased by a direct effecting on dopamine levels in the brain (Dunlop B.W. & Nemeroff C.B., 2007). Dopamine is involved in a variety of brain functions and pathways, and produces both excitatory and inhibitory postsynaptic potentials. Dopamine is synthesized in the presynaptic neuron from the amino acids phenylalanine and tyrosine. "Phasic" dopamine release is characterized by burst firing and is thought to occur in response to behavioral stimuli, such as those that may predict reward. In contrast, "tonic" dopamine release is slow and irregular. Dopamine is released from...

Rate this document

What do you think about the quality of this document?

Share this document

Let your classmates know about this document and more at