Joint scintigraphy in rabbits with 99mtc-N-[3-(triethylammonio)propyl]-15ane-N5, a new radiodiagnostic agent for articular cartilage imaging.

UNLABELLED The aim of this study was to investigate joint scintigraphy in rabbits with 99mTc-N-[3-(triethylammonio)propyl]-15ane-N5 (NTP 15-5), a new radiopharmaceutical that specifically localizes in cartilaginous tissues. METHODS Scans obtained after intravenous injection of the 99mTc-labeled compound in normal and arthropathy-induced rabbits were compared with those of the bone-imaging agent 99mTc-methylene diphosphonate (99mTc-MDP). RESULTS The radioactive uptake of 99mTc-NTP 15-5 was detected in cartilaginous tissues 5 min after injection and was stable for 2 h. The uptake intensity was related to age and joint disease severity, and cartilage alterations not revealed by radiography induced a significant decrease of radiotracer uptake. On the other hand, imaging performed with 99mTc-MDP did not reveal the early changes in arthrosis but was more specific for bone remodeling in advanced stages of diseases or in inflammatory processes. CONCLUSION Our results indicate that 99mTc-NTP 15-5 could be a good tracer for human arthrosic and arthritic cartilage detection, especially for the early diagnosis of joint diseases.