New radiolabeled CCK-8 analogues [Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8]: preparation and biodistribution studies in rats and rabbits


Ertay T., ÜNAK P., BEKİŞ R., Yurt F., Biber F., Durak H.

NUCLEAR MEDICINE AND BIOLOGY, vol.28, no.6, pp.667-678, 2001 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 28 Issue: 6
  • Publication Date: 2001
  • Doi Number: 10.1016/s0969-8051(01)00196-2
  • Journal Name: NUCLEAR MEDICINE AND BIOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.667-678
  • Keywords: peptide, cholecystokinin, CCK-8, Tc-99M-GH-CCK-8, Tc-99M-DTPA-CCK-8, DTPA, biodistribution of CCK-8, IN-VIVO, RECEPTOR SCINTIGRAPHY, BIOLOGICAL-ACTIVITY, GASTRIN RECEPTORS, CHOLECYSTOKININ, TUMORS, RADIOPHARMACEUTICALS, IDENTIFICATION, CHEMISTRY, PEPTIDES
  • Dokuz Eylül University Affiliated: Yes

Abstract

The aim of this study is to label CCK-8 with Tc-99m and to investigate its radiopharmaceutical potential. CCK-8 was labeled with Tc-99m using GH and DTPA as bifunctional chelating agents. Labeling efficiency was higher than 99%. Complex was stable more than 5 hours at room temperature. 37 MBq Tc-99m-GH-CCK-8 or Tc-99m-DTPA-CCK-8 was administered intravenously to rabbits for biodistribution experiments. Dynamic and static images were obtained from anterior projection using a Camstar XC/T gamma camera. For quantitative evaluation, regions of interest were drawn on organs and time-activity curves were generated. The highest accumulation occurred in brain within 10 and 30 minutes after injection. Renal and hepatobiliary excretion were observed. Brain distribution studies in rats showed the highest activity was in hypothalamus. Results demonstrated that Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8 analogs may be a useful new class of receptor-binding peptides for diagnosis and therapy of brain diseases related with CCK-B receptor-expressing tumors. (C) 2001 Elsevier Science Inc. All rights reserved.