Positron emission tomography study on pancreatic somatostatin receptors in normal and diabetic rats with 68Ga-DOTA-octreotide: a potential PET tracer for beta cell mass measurement.
Biochem Biophys Res Commun
; 442(1-2): 79-84, 2013 Dec 06.
Article
em En
| MEDLINE
| ID: mdl-24220338
Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia, and the loss or dysfunction of pancreatic beta cells has been reported before the appearance of clinical symptoms and hyperglycemia. To evaluate beta cell mass (BCM) for improving the detection and treatment of DM at earlier stages, we focused on somatostatin receptors that are highly expressed in the pancreatic beta cells, and developed a positron emission tomography (PET) probe derived from octreotide, a metabolically stable somatostatin analog. Octreotide was conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), a chelating agent, and labeled with (68)Gallium ((68)Ga). After intravenous injection of (68)Ga-DOTA-octreotide, a 90-min emission scan of the abdomen was performed in normal and DM model rats. The PET studies showed that (68)Ga-DOTA-octreotide radioactivity was highly accumulated in the pancreas of normal rats and that the pancreatic accumulation was significantly reduced in the rats administered with an excess amount of unlabeled octreotide or after treatment with streptozotocin, which was used for the chemical induction of DM in rats. These results were in good agreement with the ex vivo biodistribution data. These results indicated that the pancreatic accumulation of (68)Ga-DOTA-octreotide represented specific binding to the somatostatin receptors and reflected BCM. Therefore, PET imaging with (68)Ga-DOTA-octreotide could be a potential tool for evaluating BCM.
Palavras-chave
(68)Ga-DOTA-octreotide; AC; BCM; DOTA-OC; DTBZ; Diabetes mellitus; FBP; FORE; Fourier rebinning; GLP-1; ID; MAP; Pancreatic beta cell mass; Positron emission tomography; SSTR; STZ; Somatostatin receptor; VOI; adenylyl cyclase; beta cell mass; dihydrotetrabenazine; filtered back-projection; glucagon-like peptide-1; injected dose; maximum a posteriori; somatostatin receptor; streptozotocin; volumetric region of interest
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Compostos Organometálicos
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Pâncreas
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Octreotida
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Contagem de Células
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Receptores de Somatostatina
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Tomografia por Emissão de Pósitrons
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Diabetes Mellitus
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Células Secretoras de Insulina
Limite:
Animals
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article