Development of a Radiolabeled Amlodipine Analog for L-type Calcium Channel Imaging.

Purpose: The non-invasive imaging and quantification of L-type calcium channels (also known as dihydropyridine channels) in living tissues is of great interest in diagnosis of congestive heart failure, myocardial hypertrophy, irritable bowel syndrome etc.

Methods: Technetium-99m labeled amlodipine conjugate ([99mTc]-DTPA-AMLO) was prepared starting freshly eluted (<1 h) 99mTechnetium pertechnetate (86.5 MBq) and conjugated DTPAAMLO at pH 5 in 30 min at room temperature in high radiochemical purity (>99%, RTLC; specific activity: 55-60 GBq/mmol).