Tc-99m MAG3 (mercaptoacetyltriglycine) is one of the technetium radiopharmaceuticals used in renal imaging.  It largely taken up by tubular secretion.   It has a strong role in assessing the function of kidneys and in the assessment of an obstructed kidney.

DMSA is the main competiter radio-isotope renal imaging study, have a large role in the pediatric popuation.

This demonstrates a normal study (for reference) with identical uptake,excretion and curves.