Accumulation of 99mTc-Cysteine in experimental inflammatory lesions in comparison to 99mTc-glutamine and 99mTc-HIG.

Abstract

AIM:

The aim of this experimental work was to investigate the efficacy of 99mTc-L-Cysteine (Cys) in scintigraphic visualization of inflammatory lesions in comparison to 99mTc-L-glutamine (G), and 99mTc-HIG.

METHODS:

In mice abscesses were induced by intramuscular injection of turpentine. Six days later mice were injected with 3.7 MBq of each agent and sacrificed in groups of three at 1, 3, 6 and 24 h. Scintigrams were obtained with a gamma camera. The organs, some blood, abscesses, some muscle and urine were removed, weighed and counted in a gamma counter. Percentage of uptake by organs and per gram tissues and abscess/normal tissue concentration ratios were calculated. Experimental arthritis was produced in 6 New Zealand rabbits by intraarticular injection of ovalbumin. Four days later 37 MBq of 99mTc-Cys and 99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h demonstrated the arthritic joints very well. ROI's over arthritic joints were compared to contralateral normal joints (A/C).

RESULTS:

In mice the abscesses were well visualized on all scintigrams. The maximum abscess/muscle ratios were 5.21 +/- 1.09 (6 h), 3.73 +/- 0.81 (3 h) and 5.98 +/- 1.17 (24 h) and the maximum abscess/blood ratios were 3.46 +/- 1.33 (24 h), 1.81 +/- 0.10 (6 h) and 0.914 +/- 0.351 (24 h) for 99mTc-Cys, 99mTc-G, and 99mTc-HIG, respectively. In rabbits the maximum A/C ratios were 2.61 +/- 0.53 (3 h) and 2.92 +/- 0.99 (24 h) for 99mTc-Cys and 99mTc-HIG, respectively.

CONCLUSION:

Our results indicate that 99mTc-Cys is a promising agent for imaging inflammatory lesions. It is preferred to 99mTc-HIG, because of higher concentration ratios attained earlier, lower blood background, lower cost and a simpler in-house preparation method.

• Authors: M T Ercan, N C Gülaldi, U Uysal, S Unsal, M Aydin, I Peksoy, Z Hasçelik
• Journal: Nuklearmedizin. Nuclear medicine (Nuklearmedizin) Vol. 36 Issue 8 Pg. 265-9 (Dec 1997) ISSN: 0029-5566 [Print] Germany
• PMID: 17068876 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Immunoglobulins
• Organotechnetium Compounds
• technetium 99m cysteine
• technetium 99m glutamine
• technetium Tc 99m immunoglobulin
• Glutamine
• Technetium
• Cysteine

Topics

• Animals
• Arthritis, Experimental (diagnostic imaging)
• Cysteine (analogs & derivatives, pharmacokinetics)
• Disease Models, Animal
• Glutamine (analogs & derivatives, pharmacokinetics)
• Immunoglobulins
• Inflammation (diagnostic imaging)
• Knee Joint (diagnostic imaging)
• Mice
• Organotechnetium Compounds (pharmacokinetics)
• Radionuclide Imaging
• Technetium (pharmacokinetics)