Inhibition of Insulin Release by Urotensin II - A Study on the Perfused Rat Pancreas

Introduction

Urotensin-II (U-II) is a vasoactive cyclic dodecapeptide first isolated from the caudal neurosecretory system from the teleost [1], which has been recently cloned from a number of species including mouse, rat [2] and human [3].

In 1999, two groups described the identification of an orphan human G-protein-coupled receptor homologous to rat GPR14 which functions as U-II receptor [4] [5]. Sequence analysis of U-II peptides revealed that the C-terminal cyclic hexapeptide (-Cys-Phe-Trp-Lys-Tyr-Cys-) is well preserved across species [6], and is also structurally similar to a biologically active region of somatostatin-14 (-Phe-Trp-Lys-Thr-) [7].

In view of the structural analogy of U-II with somatostatin, we investigated its effect on pancreatic hormone secretion in this study, which was performed in the isolated perfused rat pancreas.

References

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