[The receptor binding study in vivo].

In vivo receptor mapping in human brain with positron emission tomography (PET) and single-photon emission tomography (SPECT) is of great value for neuropharmacology and psychiatry. However, it is unclear yet the characteristics of receptor binding in vivo, and significant discrepancies of receptor binding between in vitro and in vivo have been observed. It seems to be important to clarify the characteristics of receptor binding in vivo as compared with in vitro binding systems. In this review, procedures of receptor binding studies using small animals and 3H-labeled ligands, methodological problem as well as the kinetic analysis method are discussed.