The presence of islet amyloid polypeptide/calcitonin gene-related peptide/salmon calcitonin binding sites in the rat nucleus accumbens

doi:10.1016/0014-2999(94)90036-1

European Journal of Pharmacology

Volume 262, Issues 1–2, 1 September 1994, Pages 133-141

https://doi.org/10.1016/0014-2999(94)90036-1 Get rights and content

Abstract

Receptor autoradiographic analysis of binding in rat brain sections for [¹²⁵I]islet amyloid polypeptide (IAPP), [¹²⁵I]calcitonin gene-related peptide (CGRP) and [¹²⁵I]salmon calcitonin indicated dense binding for all three ligands in the nucleus accumbens. Membrane binding studies revealed the existence of high affinity sites for all three peptides. The order of potency of various related peptides at each binding site was investigated and found for [¹²⁵I]IAPP to be salmon calcitonin > IAPP = αCGRP > salmon calcitonin-(8–32); for [¹²⁵I]CGRP to be αCGRP > IAPP > salmon calcitonin; and for [¹²⁵I]salmon calcitonin to be salmon calcitonin > αCGRP > rat calcitonin > salmon calcitonin-(8–32) > IAPP, suggesting that [¹²⁵I]IAPP targets the CGRP₃ receptor subtype. This study confirms the existence of two receptors in therat nucleus accumbens binding salmon calcitonin, one of which binds αCGRP and IAPP with a high affinity.

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The presence of islet amyloid polypeptide/calcitonin gene-related peptide/salmon calcitonin binding sites in the rat nucleus accumbens

Abstract

Fed. Eur. Biochem. Soc.

FEBS Lett.

Trends Endocrinol. Metab.

Brain Res.

Pharmacol. Biochem. Behav.

Brain Res.

Biochem. Biophys. Res. Commun.

Life Sci.

Jpn. J. Pharmacol.

Brain Res.

Brain Res.

Jpn. J. Pharmacol.

Regul. Pept.

Jpn. J. Pharmacol.

Jpn. J. Pharmacol.

Anal. Biochem.

Brain res.