| Autor: |
C S, John, W D, Bowen, T, Saga, S, Kinuya, B J, Vilner, J, Baumgold, C H, Paik, R C, Reba, R D, Neumann, V M, Varma |
| Rok vydání: |
1993 |
| Předmět: |
|
| Zdroj: |
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 34(12) |
| ISSN: |
0161-5505 |
| Popis: |
In order to develop improved radiopharmaceuticals for imaging malignant melanoma, we have synthesized and characterized 125I-and 131I-labeled (2-piperidinylaminoethyl)4-iodobenzamide (PAB). In vitro binding profiles of IPAB and N-(2-diethylaminoethyl)4-iodobenzamide (IDAB, a structurally related analog of IPAB) for a variety of neurotransmitter receptors suggested that both IPAB and IDAB possessed a high sigma-1 affinity and a low affinity for sigma-2 sites. In vitro homologous competition binding studies of [125I]PAB with human malignant melanoma cell A2058 showed that the tracer was bound to the cells with a high affinity (Ki = 6.0 nM) and that the binding was saturable. Biodistribution studies in nude mice implanted with human malignant melanoma xenografts showed good tumor uptake (3.87% ID/g at 1 hr, 2.91% ID/g at 6 hr and 1.02% ID/g at 24 hr) of [125I]PAB. High tumor-to-nontarget organ ratios were obtained at 24 hr postinjection. Tumor-to-blood, liver, muscle, lung, intestines, heart and brain ratios at 24 hr were 17.80, 3.88, 94.58, 14.29, 10.87, 37.07 and 90.01, respectively. Tumor imaging with [131I]PAB in a nude mice model xenografted with human malignant melanoma at 24 hr clearly delineated the tumor with very little activity in any other organ. These results demonstrate that sigma-1 receptors could be used as external markers for malignant melanoma. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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