Ghrelin is a 28-amino acid octanoylated peptide hormone that is implicated in many physiological and pathophysiological processes. Specific visualization of ghrelin and its cognate receptor using traceable ligands is crucial in elucidating the localization, functions and expression pattern of the peptide's signaling pathway. Here we review 12 representative radio- and fluorescently-labeled peptide-based ligands for in vitro and in vivo imaging studies. In particular, we focus on their structural features, pharmacological properties and applications in further biochemical research.

中文翻译：

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靶向Ghrelin受体的可追溯肽配体。

Ghrelin是一种28个氨基酸的辛酰化肽激素，与许多生理和病理生理过程有关。使用可追踪的配体对生长素释放肽及其同源受体进行特定的可视化，对于阐明肽信号通路的定位，功能和表达模式至关重要。在这里，我们审查12代表性的放射性和荧光标记的基于肽的配体，用于体外和体内成像研究。特别是，我们专注于它们的结构特征，药理特性以及在进一步生化研究中的应用。