In vivo measurement of receptor density and affinity: comparison of the routine sequential method with a nonsequential method in studies of dopamine D2 receptors with [11C]raclopride.
Positron emission tomography with the dopamine D(2/3) receptor ligand raclopride was used to compare sequential (studies on 1 day) and nonsequential (different days) approaches to in vivo measurement of the density and affinity of receptors. The choice of temporal sequence of radiotracer injection over a range of specific activities might result in bias because of diverse factors. A strong concordance is reported between the outcomes of the sequential and nonsequential methods. This suggests that the characteristics of the dopamine D(2/3) receptors are relatively stable within physiologic boundaries and can be reproducibly and reliably measured in stable conditions.
Doudet
Doris J
DJ
Department of Medicine, Division of Neurology and TRIUMF, Room M36, Purdy Pavilion, University of British Columbia, 2221 Wesbrook Mall, Vancouver, BC, Canada V6T 2B5. ddoudet@interchange.ubc.ca
Jivan
Salma
S
Holden
James E
JE
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D002250:Carbon Radioisotopes; D018492:Dopamine Antagonists / Q000378:metabolism*; D005260:Female; D008253:Macaca mulatta; D008297:Male; D020891:Raclopride / Q000378:metabolism*; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D015203:Reproducibility of Results; D013997:Time Factors; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D018492:Dopamine Antagonists; D017448:Receptors, Dopamine D2; D020891:Raclopride