Interactions between agmatine and polyamine uptake pathways in rat pulmonary artery endothelial cells
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Updated: Oct 8, 2026

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
1Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, AL 36688, USA.
Abstract:
Agmatine, a product of arginine metabolism in vascular endothelial cells, is structurally similar to the natural polyamines, putrescine, spermidine and spermine. To test the hypothesis that agmatine and polyamines interacted at the level of the polyamine transporter, we determined if polyamines competed with agmatine for import and whether interventions modulating polyamine import exerted coordinate effects on agmatine uptake. Multiple lines of evidence were obtained to suggest that agmatine enters pulmonary artery endothelial cells (PAECs) via the polyamine transporter, though its intracellular disposition after uptake appears different from the natural polyamines.
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