Technetium-99m-L,L-ethylenedicysteine: a renal imaging agent. I. Labeling and evaluation in animals.
L,L-ethylenedicysteine (L,L-EC) can be labeled efficiently with 99mTc at pH 12 to obtain a highly pure and very stable tracer agent (99mTc-L,L-EC). The biological behavior of 99mTc-L,L-EC was studied in mice and a baboon. In mice, 99mTc-L,L-EC demonstrated a more rapid urinary excretion and less retention in the kidneys, the liver, the intestines, and the blood than did 99mTc-MAG3 at 10 and 60 min p.i. Urinary excretion decreased in probenecid pretreated mice, which indicates active tubular transport. In the baboon, the renograms for 99mTc-MAG3 and 99mTc-L,L-EC were comparable. Plasma-protein binding of 99mTc-L,L-EC was lower than that of 99mTc-MAG3 while its distribution volume and 1-hr plasma clearance were clearly higher. The promising results of the animal experiments suggest that 99mTc-L,L-ethylenedicysteine may be a useful alternative to 99mTc-MAG3 for renal function studies in humans.
Verbruggen
A M
AM
Laboratory of Radiopharmaceutical Chemistry I.F.W., K.U. Leuven, Belgium.
Nosco
D L
DL
Van Nerom
C G
CG
Bormans
G M
GM
Adriaens
P J
PJ
De Roo
M J
MJ
D000818:Animals; D003545:Cysteine / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D004341:Drug Evaluation; D007553:Isotope Labeling; D008297:Male; D051379:Mice; D009842:Oligopeptides; D015609:Organotechnetium Compounds / Q000097:blood / Q000493:pharmacokinetics*; D010215:Papio; D011866:Radioisotope Renography; D017263:Technetium Tc 99m Mertiatide; D014018:Tissue Distribution
D009842:Oligopeptides; D015609:Organotechnetium Compounds; C073806:technetium Tc 99m-ethylenedicysteine; D017263:Technetium Tc 99m Mertiatide; D003545:Cysteine