Radioiodinated diacylglycerol analogue: a potential imaging agent for single-photon emission tomographic investigations of cerebral ischaemia
Autor: | Satoshi Ueda, Shusaku Tazawa, Ryou Fujii, Kazuo Wakita, Yoshio Ohmori, Yoshio Imahori, Minoru Inoue |
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Rok vydání: | 1996 |
Předmět: |
Male
medicine.medical_specialty Diacylglycerol lipase Phospholipid Brain Ischemia Diglycerides Iodine Radioisotopes Rats Sprague-Dawley chemistry.chemical_compound In vivo Internal medicine medicine.artery Phosphatidylcholine Occlusion medicine Animals Radiology Nuclear Medicine and imaging Technetium Tc 99m Aggregated Albumin Diacylglycerol kinase Tomography Emission-Computed Single-Photon biology Iodobenzenes Lipid metabolism General Medicine Anatomy Rats Endocrinology chemistry Middle cerebral artery biology.protein Technetium Tc 99m Pentetate lipids (amino acids peptides and proteins) |
Zdroj: | European Journal of Nuclear Medicine. 23:280-289 |
ISSN: | 1619-7089 0340-6997 |
DOI: | 10.1007/bf00837626 |
Popis: | Phospholipid metabolism is closely related to membrane perturbation in cerebral ischaemia. We investigated in vivo topographical lipid metabolism using an iodine-123-labelled diacylglycerol analogue, (1-(15-(4-iodine-123-iodophenyl)-pentadecanoyl)-2-stearoyl-rac-gly cerol) (123I-labelled DAG), in a middle cerebral artery (MCA) occlusion model with the aim of positive imaging of ischaemic insult. Sprague-Dawley rats underwent coagulation of the MCA to induce permanent occlusion. MCA occlusion times prior to injection of 123I-labelled DAG ranged from 15 min to 14 days. Each rat was injected with 11-37 MBq of 123I-labelled DAG via a tail vein. After 30 min, in vivo autoradiographs were reconstructed. Scanning of the living rat brain in this MCA occlusion model was performed using a gamma camera with a pinhole collimator. Cerebral infarctions were recognized in the frontal cortex, the parietal cortex and the lateral portion of the caudate-putamen by 2,3,5-triphenyltetrazolium hydrochloride staining. In infarcted regions (region 1), 123I-labelled DAG incorporation showed a slight decrease up to 12 h; it then increased up to 6 days and decreased thereafter. In peri-infarcted regions (region 2), the incorporation showed almost no change up to 12 h, then increased up to 5-6 days and decreased thereafter. In other regions (region 3), the incorporation showed no change. Lipid analysis showed that 123I-labelled DAG was metabolized to 15-(4-iodine-123-iodophenyl)-pentadecanoic acid by DAG lipase and to 123I-labelled phosphatidylcholine. Scanning of the ischaemic region showed higher accumulation than on the non-lesioned side. We established a method to visualize ischaemic foci as positive images. The early changes in 123I-labelled DAG incorporation were closely related to DAG lipase, which degraded the accumulated intrinsic DAG, and increased 123I-labelled DAG incorporation in the chronic stage involves several aspects of neural destruction in the process of autolysis. It is concluded that the reported method could have a clinical future. |
Databáze: | OpenAIRE |
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