Details

Autor(en) / Beteiligte

• Demaegdt, Heidi
• Lukaszuk, Aneta
• de Buyser, Evi
• de Backer, Jean-Paul
• Szemenyei, Erzsébet
• Tóth, Géza
• Chakravarthy, Sridhara
• Panicker, Mitradas
• Michotte, Yvette
• Tourwé, Dirk
• Vauquelin, Georges

Titel

Selective labeling of IRAP by the tritiated AT receptor ligands [H]Angiotensin IV and its stable analog [H]AL-11

Ist Teil von

• Molecular and cellular endocrinology, 2009-09, Vol.311 (1-2)

Ort / Verlag

Elsevier

Erscheinungsjahr

2009

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ‘AT receptors' through which angiotensin IV (Ang IV) improves memory acquisition, were recently identified as insulin regulated aminopeptidase (IRAP). Radioligand binding studies have hitherto been performed with iodinated Ang IV in the presence of divalent cation chelators EDTA and 1,10-phenanthrolin. Hence, they referred to the apo-form of IRAP. Presently, binding of [H]Ang IV and [H]AL-11, a stable Ang IV analog, was compared on Chinese hamster ovary (CHO-K1) and mouse hippocampal (P40H1) cell membranes. With chelators, their high affinity sites showed the same pharmacological profile as for [I]Ang IV binding. Without chelators, only high affinity binding was perceived for [H]AL-11. The same pharmacological profile was recorded in both membrane preparations; it was different from the one in presence of chelators and corresponded to catalytically active IRAP (despite the concurrent presence aminopeptidase N (APN) in P40H1 cell membranes). This confirms that the active and apo-forms of IRAP have a distinct pharmacological profile.