Receptor scintigraphy with a radioiodinated somatostatin analogue: Radiolabeling, purification, biologic activity, and in vivo application in animals

Journal Article · Sat Sep 01 04:00:00 EDT 1990 · Journal of Nuclear Medicine; (USA)

OSTI ID:6421796

Bakker, W H; Krenning, E P; Breeman, W A; Koper, J W; Kooij, P P; Reubi, J C; Klijn, J G; Visser, T J; Docter, R; Lamberts, S W ^[1]

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1. University Hospital Dijkzigt, Rotterdam (Netherland)

Radioiodinated Tyr-3-octreotide, a somatostatin analogue, is a useful ligand for the in vitro detection of somatostatin receptors. In this study, we have investigated the possible in vivo application of this radioligand in the detection of somatostatin receptor-bearing tumors by scintigraphy. The specific somatostatin-like biologic activity of radioiodinated Tyr-3-octreotide was confirmed in vitro: (a) radioiodinated Tyr-3-octreotide competes in the nanomolar range with specific receptor binding of somatostatin to suspended human meningioma membranes and (b) the secretion of growth hormone by cultured rat pituitary cells was similarly inhibited by iodinated Tyr-3-octreotide and somatostatin. In rats, intravenously injected {sup 123}I-Tyr-3-octreotide is rapidly cleared from the circulation mainly by the liver. Although this rapid clearance limits the amount of tracer available for somatostatin receptor-bearing tumors, the advantage of this rapid clearance is that the background level is rapidly reduced in favor of scintigraphic imaging of these tumors. Pancreatic tumors in rats were localized by scintigraphy after intravenous injection of {sup 123}I-Tyr-3-octreotide.

• OSTI ID: 6421796
• Journal Information: Journal of Nuclear Medicine; (USA), Journal Name: Journal of Nuclear Medicine; (USA) Vol. 31:9; ISSN 0161-5505; ISSN JNMEA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BIOCHEMICAL REACTION KINETICS
BODY
CLEARANCE
DIAGNOSIS
DIGESTIVE SYSTEM
DISEASES
DRUGS
ENDOCRINE GLANDS
EVALUATION
GLANDS
IN VITRO
KINETICS
LABELLED COMPOUNDS
LIGANDS
MAMMALS
MAN
MEMBRANE PROTEINS
NEOPLASMS
ORGANIC COMPOUNDS
ORGANS
PANCREAS
PRIMATES
PROTEINS
RADIOPHARMACEUTICALS
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SOMATOSTATIN
VERTEBRATES