Ligands and tracers for PET studies of the 5-HT system--current status

The status of the radiochemical development and biological evaluation of radioligands and tracers for PET studies of the serotonergic system is reviewed, indicating those agents with present value and those with future potential. Practical recommendations are given for the preparation of two useful radioligands for PET studies of central 5-HT2 receptors, namely [18F]setoperone and [18F]altanserin. Though, it has not proved possible to recommend tracers or radioligands for the study of other aspects of serotonergic system, prospects for future radiochemical development are indicated, especially for developing radioligands for the 5-HT re-uptake site, and for the 5-HT1 and 5-HT3 receptors.