ABSTRACT
Since the availability of high affinity, high specific activity neuroreceptor ligands, it has been possible to determine the spatial distribution and semiquantitative regional concentrations of some neuroreceptors using in vivo labeling methods in experimental animals. 1-9 This technique offers a natural extension to the in vivo, noninvasive study of neuroreceptors in man using emission computed tomography and appropriate receptor ligands labeled with gamma-emitting radionuclides. Since autopsy studies have already demonstrated abnormal regional receptor concentrations in people with certain neuropsychiatric diseases (see Chapter 6), the noninvasive study of neuroreceptors in man has a real potential for elucidating the etiology of neuropsychiatric disease, redefining certain specific disease states, following their natural history and their response to various therapeutic modalities.
