Blood platelets as a peripheral marker for the central serotonin system

Publisher Website
Google Scholar
Abstract
Platelet 5-HT uptake rate, 3H-imipramine binding and monoamine oxidase activity are reviewed and compared with those of preparations of nerve endings (synaptosomes). The properties of the 5-HT uptake mechanisms in platelet and brain seem to be very similar in most respects and the platelets therefore provide a useful model for brain 5-HT uptake. There is evidence both of genetic, stable control of the uptake and of a state-dependent modifying influence. The findings of some recent studies regarding the platelet 5-HT uptake rates in various psychiatric disorders are reviewed. A consistent finding seems to be a lower Vmax in patients with unipolar depression than in controls. The 3H-imtpramine binding also shows characteristics very similar to that of brain synaptosomes. Although this receptor is functionally linked to 5-HT uptake the density of imipramine binding (Bmax). is obviously independent of 5-HT uptake rates. In the case of imipramine binding the evidence for some form of constitutional (trait-dependent) control is even weaker than for 5-HT uptake. The review of findings in patients suffering from psychiatric disorders shows a confusing situation without a firmly established pattern. Platelet monoamine oxidase activity (MAO) seems to be a stable constitutional factor with a clear correlation to personality traits such as sensation-seeking, extraversion and impulsiveness, which might also explain connections with disorders such as alcoholism, psychopathy and suicidal behaviour. There are several findings which support the hypothesis that platelet MAO activity is a marker for the density or capacity of the central serotonin system. □ Blood platelets, serotonin, 5-HT3H-imipramine binding, MAO.

This publication has 79 references indexed in Scilit: