[11C]-verapamil

[11C]-verapamil is a carbon-11 radiolabeled small molecule radiotracer used in positron emission tomography (PET) imaging to evaluate the function of P-glycoprotein (P-gp) at the blood-brain barrier. While verapamil is traditionally known as a calcium channel blocker, its radiolabeled form—specifically the (R)-enantiomer—is utilized as a diagnostic probe because it is a potent substrate for the P-gp efflux transporter. Developed for clinical research at institutions such as Seoul National University Hospital, this tracer is used to investigate the transporter hypothesis of drug-resistant epilepsy. This hypothesis suggests that the overexpression of P-gp at the blood-brain barrier prevents antiepileptic drugs from reaching therapeutic concentrations in the brain. In clinical trials, [11C]-verapamil PET is often performed both at baseline and during the infusion of a P-gp inhibitor like cyclosporin A to quantify the regional expression and activity of the transporter in patients with epilepsy compared to healthy controls.

Other names

Carbon-11 verapamilCarbon11 verapamilCarbon 11 verapamil(R)-[11C]verapamil[11C]-verapamil-Seoul National University Hospital-epilepsy