TY - JOUR T1 - Angiotensin IV displays only low affinity for native insulin-regulated aminopeptidase (IRAP). JF - Fundam Clin Pharmacol Y1 - 2012 A1 - Heidi Demaegdt A1 - Jean-Paul De Backer A1 - Aneta Lukaszuk A1 - Géza Tóth A1 - Erzsébet Szemenyei A1 - Dirk Tourwé A1 - Georges Vauquelin KW - Angiotensin II KW - Animals KW - CD13 Antigens KW - Cell Line KW - Chelating Agents KW - Cho Cells KW - Cricetinae KW - Cricetulus KW - Cystinyl Aminopeptidase KW - mice KW - Organophosphorus Compounds KW - Radioligand Assay KW - Tyrosine KW - Zinc AB -

Radioligand binding studies revealed that Ang IV binds to insulin-regulated aminopeptidase (IRAP)/'AT(4) receptors' with high affinity. Yet, as these experiments were routinely carried out in the presence of chelators, only the catalytic zinc-depleted apo-form of IRAP was labelled. While the chelators remove the catalytic zinc from IRAP and protect Ang IV from proteolytic degradation, the aminopeptidase N selective inhibitor '7B' only exerts the latter effect. By using 7B along with the new stable Ang IV-analog [(3) H]AL-11, we here show that the native enzyme is only a low-affinity target for Ang IV.

VL - 26 CP - 2 M3 - 10.1111/j.1472-8206.2011.00948.x ER -