The 3.alpha. isomer of RTI-55, RTI-352, is an effective in vivobinding ligand that reflects greater selectivity for the dopaminetransporter than is observed with RTI-55. In addition, there isalso a more rapid achievement of apparent equilibrium in thestriatal-to-cerebellar ratio (compared to RTI-55) as the ratiopeaks at about 30 min and is maintained for about 20 minthereafter. Such apparent equilibrium is useful in developing anapproach to measuring the number of dopamine transporters presentin tissues. Moreover, these results indicate that the utilizationof 3.alpha. isomers of a variety of 3.beta.-(substitutedphenyl)tropanes will result in greater selectivity for dopaminetransporters and a more rapid of achievement of apparentequilibrium.
Dopamine transporter imaging ligand
Kuhar, MJ., Carroll, F., Boja, JW., Lewin, A., & Abraham, P. (2002). IPC No. U.S. Dopamine transporter imaging ligand. (U.S. Patent No. 6358492).