This review assesses some of the important advances that have been made in our understanding of the psychopathology of depression. While the monoamine theory, that postulates dysfunctional noradrenergic and serotonergic systems as the underlying cause of depression, has been valuable in the development of conventional antidepressants that are thought to act by reversing these dysfunctional states, recent clinical and experimental studies have questioned this reductionist view of depression. This has led to an assessment of the role of dysfunctional endocrine and immune systems in the aetiology of depression. In addition to explaining the link between defective neurotransmitter function and the symptoms of depression, changes in the endocrine and immune axes also help to explain the link between major depression and physical ill health. In addition, experimental and clinical studies have extended the possible involvement of neurotransmitters to include the glutamate and GABA systems. Such approaches may stimulate the development of new types of antidepressants that hopefully will combine increased efficacy with shorter speed of onset and improved side effect profiles.
2007 Prous Science