Related Experiment Video
Updated: Aug 8, 2025

An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment
Published on: December 3, 2020
Biological Distribution after Oral Administration of Radioiodine-Labeled Acetaminophen to Estimate Gastrointestinal
Kakeru Sato1, Asuka Mizutani2, Yuka Muranaka1
1Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan.
Abstract:
We evaluated the whole-body distribution of orally-administered radioiodine-125 labeled acetaminophen (125I-AP) to estimate gastrointestinal absorption of anionic drugs. 125I-AP was added to human embryonic kidney (HEK)293 and Flp293 cells expressing human organic anion transporting polypeptide (OATP)1B1/3, OATP2B1, organic anion transporter (OAT)1/2/3, or carnitine/organic cation transporter (OCTN)2, with and without bromosulfalein (OATP and multidrug resistance-associated protein (MRP) inhibitor) and probenecid (OAT and MRP inhibitor). The biological distribution in mice was determined by oral administration of 125I-AP with and without bromosulfalein and by intravenous administration of 125I-AP. The uptake of 125I-AP was significantly higher in HEK293/OATP1B1, OATP1B3, OATP2B1, OAT1, and OAT2 cells than that in mock cells. Bromosulfalein and probenecid inhibited OATP- and OAT-mediated uptake, respectively. Moreover, 125I-AP was easily excreted in the urine when administered intravenously. The accumulation of 125I-AP was significantly lower in the blood and urinary bladder of mice receiving oral administration of both 125I-AP and bromosulfalein than those receiving only 125I-AP, but significantly higher in the small intestine due to inhibition of OATPs and/or MRPs. This study indicates that whole-body distribution after oral 125I-AP administration can be used to estimate gastrointestinal absorption in the small intestine via OATPs, OATs, and/or MRPs by measuring radioactivity in the urinary bladder.
More Related Videos
09:49A Whole Body Dosimetry Protocol for Peptide-Receptor Radionuclide Therapy PRRT: 2D Planar Image and Hybrid 2D+3D SPECT/CT Image Methods
Published on: April 24, 2020
06:52Positron Emission Tomography Using 64-Copper as a Tracer for the Study of Copper-Related Disorders
Published on: April 28, 2023
Related Concept Videos
Methods for Studying Drug Absorption: In situ
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...
One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation
On...
Methods for Studying Drug Absorption: In vitro
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...
Factors Influencing Drug Absorption: Anatomical Parameters
Drug Absorption: Factors Affecting GI Absorption
Imaging Studies II: Positron Emission Tomography and Scintigraphy
Fundamental Principles of PET