抄録
Information on the delineation of the sites and mechanisms of drug action is fundametal to drug discovery and development in the central nervous system. Because this information can be obtained noninvasively, nuclear medical imaging using molecules labeled with gammma-emitting radionuclide is advantageous. Furthermore, since repetive evaluation of the information in the same object can be achieved, this method can also promptly nullify variations within individual body systems. In nuclear medical imaging system, there have recently been a rapid increase in technological advances and the high-resolution system for animals have developed. The application of the system to basic research will provide a leap ininformation on the drug action in the brain. The most straightforward approach is to radiolabel a drug and then to trace its anatomical distribution and binding in the brain. Another approach is to study how the unlabeled drug influences the physiological function measured with a radiolabeled compound (blood flow, glucose metabolism, etc.) and inhibits specific radioligand binding. The use of nuclear imaging system will demonstrate quantitative relationships between drug binding in vivo and drug effects and validate targets and mechanism for drug action in the brain.
