Measurement of neurotransmitter receptors by positron emission tomography: focus on the opiate receptor.

In summary, it is now possible to image the distribution of several neurotransmitter receptors by PET. When quantitative estimates of receptor number and affinity can be made, it will be important to study (1) changes in receptor number or affinity as a function of disease, (2) changes in receptor occupancy by endogenous neurotransmitters, and (3) changes in receptor occupancy and correlation with behavior during drug treatment.