99mTc-2GAM: a tracer for renal imaging.
We propose a renal imaging agent, the 99mTc complex of the bidentate-N,S chelate N-(mercaptoacetyl)glycine (99mTc-2GAM), with the imaging characteristics of 99mTc-DMSA but a faster kidney uptake; chemical evidence supports the formulation of 99mTc-2GAM as [Tc(v)(O)(GAM)2]-. After biodistribution and toxicity studies in animals, 99mTc-2GAM was evaluated in five normal volunteers. 99mTc-2GAM is rapidly cleared from the blood (t1/2 = 9 min) and 50% of the ID is excreted in the urine in the first 2 h. Dynamic data show a rapid renal uptake that increases up to 1 h with no significant wash-out between 1 and 8 h. The uptake in each kidney ranges from 11.3% to 20.7% ID. Low, stable liver uptake is observed. No significant activity is detected in other organs. We showed no differences between 99mTc-2GAM and 99mTc-DMSA compared in three patients with unilateral kidney disease. We conclude that 99mTc-2GAM has good practical and dosimetric features for renal imaging.
Gianolli
L
L
INB-CNR, University of Milan, Department of Nuclear Medicine, H San Raffaele, Italy.
Dosio
F
F
Matarrese
M
M
Colombo
F
F
Cutler
C
C
Stepniak-Biniakiewicz
D
D
Deutsch
E
E
Savi
A
A
Lucignani
G
G
Fazio
F
F
D000328:Adult; D000818:Animals; D005260:Female; D005998:Glycine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000493:pharmacokinetics; D006801:Humans; D007553:Isotope Labeling; D007668:Kidney / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008297:Male; D051379:Mice; D015609:Organotechnetium Compounds / Q000138:chemical synthesis* / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000493:pharmacokinetics*; D051381:Rats; D004113:Succimer / Q000493:pharmacokinetics; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D014018:Tissue Distribution
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C106066:technetium Tc 99m bidentate-N,S chelate N-(mercaptoacetyl)glycine; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D004113:Succimer; D005998:Glycine