Original scientific paper

Binding of Dihydroergosine to 5-HT_1A Receptors of Human and Rat Brain

Dorotea Mück-Šeler ; Ruđer Bošković Institute, Division of Molecular Medicine, Laboratory for Molecular Neuropharmacology, P.O.B. 180, 10002 Zagreb, Croatia
Danka Peričić ; Ruđer Bošković Institute, Division of Molecular Medicine, Laboratory for Molecular Neuropharmacology, P.O.B. 180, 10002 Zagreb, Croatia

Abstract

Interaction of the ergot alkaloid dihydroergosine with the binding of (3H)8-hydroxy-2-(di-n-propylamino)tetralin (3H8-OH-DPAT), a selective agonist for 5-HT_1A binding sites, to hippocampal membra-nes isolated from human and rat brain was studied. Competition binding experiments showed that dihydroergosine is a potent dis-placer of (3H)8-OH-DPAT binding at brain 5-HT_1A receptors of both species. Scatchard analysis of (3H)8-OH-DPAT binding to rat hippocampal membranes in the presence of dihydroergosine revealed that this ergot compound markedly decreases the number and the affinity of hippocampal (3H)8-OH-DPAT labelled binding sites. Pre-incubation of rat hippocampal membranes for 180 min with dihy-droergosine (2 nmol dm-3) completely prevented the binding of (3H)8-OH-DPAT (2 nmol dm-3). The data suggest that dihydroergo-sine is approximately as potent a ligand as 8-OH-DPAT for the hippocampal 5-HT_1A receptors from human and rat brains, although their kinetics of association and dissociation are apparently different.

Keywords

ergot alkaloid; 5-HT_1A receptors; (³H)8-OH-DPAT binding; hippocampus; human brain; rat brain

Hrčak ID:

127499

URI

https://hrcak.srce.hr/127499

Publication date:

4.2.2002.

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