| Autor: |
J. Sartor, Hans Bender, H. J. Biersack, Paul O. Zamora, D. Diekmann, Furn F. Knapp, A. Schaffland, Stefan Guhlke |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
Nuclear Medicine and Biology. 25:621-631 |
| ISSN: |
0969-8051 |
| DOI: |
10.1016/s0969-8051(98)00025-0 |
| Popis: |
Either radiolabeled Tc-99m- or Re-188-labeled MAG 3 -4-nitrophenylester or unlabeled Bz-MAG 3 -4-nitrophenylester was reacted with amines and peptides to follow a pre- or a postconjugate radiolabeling route, respectively. The model compounds were N ′- t -butyloxycarbonyl-1,6-diaminohexane (DH-Boc) and a Lysprotected derivative of the somatostatin analog RC-160 (cyclic D-Phe-Cys-Tyr-d-Trp-Lys-Val-Cys-Trp-NH 2 ). In the case of labeling DH-Boc, both the preconjugate labeling and the postconjugate labeling were found by using analytical HPLC to provide identical radiolabeled compounds regardless whether Re-188 or Tc-99m was used. The results are supported by infrared and mass-spectral data obtained from compounds synthesized using stable rhenium. The 188 Re- or 99m Tc-MAG 3 -RC-160 somatostatin analog were synthesized following the preconjugate labeling route and subsequent removal of the protecting group. Biodistributions of 188 Re- and 99m Tc-MAG 3 -RC-160 were evaluated in normal and tumor-bearing mice, and were similar to those of radioiodinated 131 I-RC-160. All radiolabeled analogs of RC-160 were rapidly cleared from the blood and were excreted through the hepatobiliary system with very little normal organ uptake. The tumor uptake (PC-3, human prostate adenocarcinoma) of systemically administered Re-188-MAG 3 -RC160 was very low, and it reached only 0.28% injected dose/g (%IDg) at 24 h postinjection, similar to what was obtained with I-131-RC-160. Intratumor injections resulted in significant tumor retentions (9.3% ID/g at 24 h). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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