[Serotoninergic depression--hypothesis or reality?]

Could we use the term "serotoninergic depression"? To answer this question various tests that seem to confirm the serotoninergic hypothesis of depression are described and their respective value ascertained. The measure of 5 HIAA (5 hydroxy indole acetic acid) in the cerebrospinal fluid has made it possible to isolate a population of depressed people with a low rate of this main metabolite of serotonin. This test seems to be linked with the frequency and the severity of attempts to commit suicide. The tryptophane, the direct serotonin's precursor, is reduced among some depressed people, for whom it could be used as a therapy. Blood platelet is used as a peripheral model of serotoninergic neuron; present research highlight among depressed people, decrease of serotonin uptake, of binding of tritiated imipramine, of monoamine oxidase, and of serum serotonin levels. Results analysis has been made difficult because of a lack of homogeneous methodologies: classification systems of depressions differ and the composition of test groups do not take into account physiological factors. In spite of these difficulties, we can try to describe the "serotoninergic depression" and consider this notion as a model for research.