RT Journal Article
SR Electronic
T1 Role of (Drug) Transporters in Imaging in Health and Disease
JF Drug Metabolism and Disposition
JO Drug Metab Dispos
FD American Society for Pharmacology and Experimental Therapeutics
SP 2007
OP 2015
DO 10.1124/dmd.114.059873
VO 42
IS 12
A1 Bruno Stieger
A1 Jashvant D. Unadkat
A1 Bhagwat Prasad
A1 Oliver Langer
A1 Hariprasad Gali
YR 2014
UL http://dmd.aspetjournals.org/content/42/12/2007.abstract
AB This report is the summary of presentations at the symposium sponsored by the American Society for Pharmacology and Experimental Therapeutics, April 26–30, at Experimental Biology 2014 in San Diego, CA. The presentations focused on the role of transporters in imaging in health and disease and on assessing transporter function in vivo. Imaging is an important diagnostic tool in clinics and is a novel tool for in vivo visualization of transporter function. Many imaging substrates and endogenous markers for organ function are organic anions. In this symposium, the bile salt transporter sodium taurocholate cotransporting polypeptide and the liver organic anion transporting polypeptides (OATPs) as well as the renal organic anion transporters (OATs) were addressed in detail; e.g., OATPs mediate transport of contrast agents used for magnetic resonance imaging of the liver or transport agents used for hepatobiliary scintigraphy, and OATs transport substances used in renography. In addition, the symposium also focused on the multidrug-resistance transporter 1 (MDR1 or P-gp), which is the most important gatekeeper in epithelial or endothelial barriers for preventing entry of potentially harmful substances into organs. Novel substrates suitable for positron emission tomography (PET) allow the study of such transporters at the blood-brain barrier or while they are mediating uptake of drugs into hepatocytes, and, importantly, PET tracers also now allow renography. Finally, quantitative data on transporter expression in human organs allow the development of improved physiologically based pharmacokinetic (PBPK) models for drug disposition. Hence, the combined efforts using novel substrates for in vivo visualization of transporters and quantification of transporters will lead to a deeper understanding of transporter function in disease and allow development of novel PBPK models for disease states.