OctreoScan 111 for imaging of a somatostatin receptor-positive islet cell tumor in rat.

Somatostatin (SRIF) receptors are present in a variety of human tumors such as pituitary and endocrine pancreatic tumors, brain tumors, small cell lung cancers and malignant breast tumors. The 111In-labeled SRIF analog SDZ 215-811 (OctreoScan 111) binds with a high affinity to somatostatin receptors and exhibits SRIF-like biological properties, as demonstrated by the inhibition of growth hormone release from pituitary cells. We report here the in vitro characterization of SDZ 215-811 and the in vivo imaging of an islet cell tumor grown in rats using [111In]SDZ 215-811. In vitro autoradiographies revealed a high density of SRIF receptors on the pancreatic tumor tissue. As early as 5 min after intravenous injection of [111In]SDZ 215-811 into tumor-bearing rats, the tumors were clearly localized by gamma-camera scintigraphy. Even 24 h post injection, the islet cell tumor was still detectable. The radioligand was mainly cleared from the circulation via the kidneys, with a rapid alpha-phase (t1/2 = 5.6 min) and a slow elimination phase (t1/2 = 7.3 h). Biodistribution studies revealed a relatively high accumulation of radioactivity in the kidneys, but low uptake into the liver and the intestine. High uptake of [111In]SDZ 215-811 was observed for the tumor tissue (0.92 +/- 0.07% ID/g; 1 h post injection). Interestingly, a tumor load of 0.14 +/- 0.01% ID/g was still measured after 24 h. The tumor/blood ratio was 4.93 after 24 h, indicating specific accumulation of radioactivity in the islet cell tumor.(ABSTRACT TRUNCATED AT 250 WORDS)
AuthorsC Bruns, B Stolz, R Albert, P Marbach, J Pless
JournalHormone and metabolic research. Supplement series (Horm Metab Res Suppl) Vol. 27 Pg. 5-11 ( 1993) ISSN: 0170-5903 [Print] GERMANY
PMID8392488 (Publication Type: Journal Article)
Chemical References
  • Indium Radioisotopes
  • Iodine Radioisotopes
  • Receptors, Somatostatin
  • SDZ 215-811
  • Pentetic Acid
  • SDZ 204-090
  • Octreotide
  • Adenoma, Islet Cell (radionuclide imaging)
  • Animals
  • Indium Radioisotopes
  • Iodine Radioisotopes
  • Octreotide (analogs & derivatives, metabolism, pharmacokinetics)
  • Pancreatic Neoplasms (radionuclide imaging)
  • Pentetic Acid (analogs & derivatives)
  • Rats
  • Receptors, Somatostatin (analysis, metabolism)
  • Tissue Distribution

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: