Structure biodistribution relationship of radioiodinated tropeines: Search for a molecular probe for the characterization of the cocaine receptor

✍ Scribed by Garo P. Basmadjian; Stanley L. Mills; Mangesh Kanvinde; Nareg P. Basmadjian

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: French
• Weight: 528 KB
• Volume: 28
• Category: Article
• ISSN: 0022-2135
• DOI: 10.1002/jlcr.2580280709

✦ Synopsis

Abstract

Three iodinated analogs of cocaine were synthesized and radiolabeled by isotope exchange in the presence of Cu^++^ using a “kit” procedure. 2′‐Iodococaine,2′‐iodotropacocaine and 2′‐iodobenzoyl tropine radiolabeled with ^125^I were injected in mice and their biodistribution studied. Activity with all three radiolabeled compounds peaked in the brain and heart between 5 and 30 min. post injection. Activity from ^125^I‐2′‐iodococaine (S.A.=468 mCi/mmol), peaked in the brain at 15 min (2.38% injected dose/g) and showed a plateau in the heart between 5 and 60 min post injection (1.67–2.16%). ^125^I‐2′‐iodotropacocaine (S.A.=407 mCi/mmol) at 5 min had the highest uptake in the brain (8.16%) and the heart (4.44%) while activity from ^125^I‐2′‐iodobenzoyl tropine (S.A.=407 mCi/mmol) peaked in the brain at 15 min (4.19%) and at 5 min in the heart (3.33%). The biodistribution of ^125^I‐2′‐iodococaine paralleled literature values obtained with ^3^H‐/^14^C‐cocaine. We conclude that radioiodinated tropeines radiolabeled with ^123^I may be developed into useful probes to examine and characterize the cocaine receptor in‐vivo by SPECT imaging.