神经降压素是一种调节肽，可以作为不同类型的正常细胞和癌细胞的生长因子。神经降压素与相关受体的结合通过改变细胞内酶活性导致细胞增殖、存活、迁移和侵袭。因此，基于神经降压素的放射性肽的设计在神经降压素受体阳性肿瘤的靶向成像或治疗中发挥着重要作用。合成了 [Lys8]-神经降压素 (7-13) 肽并通过接头连接到 HYNIC 作为螯合剂。使用 99mTc 作为放射性核素和 EDDA/tricine 作为共配体，在 100°C 下进行标记程序 10 分钟。使用 RTLC 和 HPLC 方法测定人血清中标记肽的稳定性。使用 HT-29 结肠癌细胞研究了受体结合内化，并在携带 CT-26 肿瘤的小鼠中评估了组织生物分布。 [99mTc]Tc-Tricine/EDDA/HYNIC-GABA-[Lys8]-神经降压素 (7-13) 肽的标记率超过 98%，比活性为 37.00GBq/μmol，在人血清中具有高稳定性， Kd 的纳摩尔范围，注射后 1 小时肿瘤摄取为 0.36 ± 0.15% ID/g。这些结果表明，标记的肽是神经降压素受体阳性肿瘤的合适成像剂。版权所有 © 2024 Elsevier Inc. 保留所有权利。

Neurotensin is a regulatory peptide that can act as a growth factor on different types of normal and cancerous cells. Binding of Neurotensin to relevant receptors leads to cell proliferation, survival, migration and invasion by changing intracellular enzyme activity. Therefore, the design of a neurotensin-based radiopeptide plays an important role in targeted imaging or therapy of neurotensin receptor-positive tumors. A [Lys8]-neurotensin (7-13) peptide was synthesized and attached to HYNIC as a chelator via a linker. The labeling procedure was carried out at 100 °C for 10 min using 99mTc as a radionuclide and EDDA/tricine as coligands. Stability of the labeled peptide in human serum was determined using RTLC and HPLC methods. The receptor binding internalization was studied using HT-29 colon carcinoma cells, and tissue biodistribution was evaluated in mice bearing CT-26 tumors. The [99mTc]Tc-Tricine/EDDA/HYNIC-GABA-[Lys8]-neurotensin (7-13) peptide demonstrated a labeling yield of over 98 %, a specific activity of 37.00 GBq/µmol, high stability in human serum, a nanomolar range of Kd, and a tumor uptake of 0.36 ± 0.15 % ID/g at 1-h post-injection. These results suggest that the labeled peptide is a suitable imaging agent for neurotensin receptor-positive tumors.Copyright © 2024 Elsevier Inc. All rights reserved.