Effect of Carboxyl-Group of D-Glutamic Acid or [gamma]-Carboxy-D-glutamic Acid as N-Terminal Amino Acid of 111In-Diethylenetriaminepentaacetic Acid-Octreotide on Accumulation of Radioactivity in Kidney

• Published in: Biological & pharmaceutical bulletin Vol. 30; no. 11; p. 2226
• Main Authors: Akizawa, Hiromichi, Saito, Madoka, Tsukamoto, Ikuko, Ohkura, Tatsuya, Shimizu, Takaya, Kitamura, Youji, Mifune, Masaki, Saito, Yutaka, Arano, Yasushi, Saji, Hideo
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Science and Technology Agency 01.11.2007
• ISSN: 0918-6158; 1347-5215

To establish a strategy for developing 111In-diethylenetriaminepentaacetic acid (111In-DTPA)-octreotide, a diagnostic radiopharmaceutical agent for tumors, with reduced non-specific renal radio-accumulation, the compounds having D-glutamic acid (Glu) or γ-carboxy-D-glutamic acid (carboxy-Glu) as the N-terminal amino acid were examined for in vivo radio-distribution. Compounds carrying Glu and carboxy-Glu containing one and two negative charges, respectively, showed lower renal radio-accumulation than that carrying D-phenylalanine. It was revealed that the introduction of a negative charge reduces the renal radio-accumulation independently from the number of negative charges. The present result can be a clue for the development of 111In-DTPA-octreotides with reduced the renal radio-accumulation.