ABSTRACT
The biological characteristics of a radiolabeled metalloporphyrin, 5,10,15,20-tetrakis(4-carboxyphenyl)-porphinato [67Cu]copper (II) [( 67Cu]TCPP), in rat lymph nodes, surrounding muscle, fat, and blood were determined. Lymphatic tissue localized greater amounts of [67Cu]TCPP than did surrounding muscle and fat. Inflamed lymph nodes localized greater amounts of [67Cu]TCPP than did noninflamed lymph nodes. Time course studies suggest that the uptake of [67Cu]TCPP in noninflamed and in inflamed lymph nodes may involve different biological processes. The affinity of [67Cu]TCPP for inflamed lymph nodes may be influenced by the degree of inflammation. If further studies confirm these results, [67Cu]TCPP may be useful as a potential radiopharmaceutical for imaging inflamed lymph nodes.
Subject(s)
Lymph Nodes/metabolism , Metalloporphyrins/pharmacokinetics , Adipose Tissue/metabolism , Animals , Copper Radioisotopes , Lymphadenitis/metabolism , Male , Metalloporphyrins/blood , Muscles/metabolism , Rats , Rats, Inbred F344ABSTRACT
A series of experiments compared the uptake of 5,10,15,20 tetrakis(4-carboxyphenyl) porphinato [67Cu] copper (II), 67CuTCPP, by the lymph nodes of inflamed and two sets or control rats. The results demonstrate that 67CuTCPP localizes in greater concentration in inflamed lymph nodes than in noninflamed control lymph nodes. This enhanced uptake of 67CuTCPP by inflamed lymph nodes was 3.6 times greater than was the uptake by control lymph nodes. A time course study demonstrated that the uptake of 67CuTCPP by inflamed lymph nodes reached the maximum level by 24 hours post-injection of 67CuTCPP and remained constant throughout the 96 hours examined. It was also found that the uptake of 67CuTCPP by inflamed lymph nodes was not exclusively dependent upon an increase in the weight of inflamed lymph nodes. These studies show that 67CuTCPP has potential as a lymphoscintigraphy agent.
