Hemorphins inhibit angiotensin IV binding and interact with aminopeptidase N

Isabelle Garreau (1) , Dominique Chansel (2) , Sophie Vandermeersch (2) , Ingrid Fruitier (1) , Jean Marie Piot (1) , Raymond Ardaillou (2)

1 LGPC - Laboratoire de Génie Protéique et Cellulaire
2 Des Maladies Rénales Rares aux Maladies Fréquentes, Remodelage et Réparation

[125I]-Ang IV binding to rabbit collecting duct cell membranes was inhibited by hemorphins (H), a class of endogenous peptides obtained by hydrolysis of the beta chain of hemoglobin. The most potent competitors were those with a valine in their N-terminal part such as LVV-H7 and VV-H7 (IC50 = 1.3 nM) followed by VV-H8 and K6VV-H7 (5.1 nM). The same H, like Ang IV, interacted with aminopeptidase N (APN) as shown by their inhibitory effect (28-36%) on APN activity. HPLC analysis showed that only H with a N-terminal valine or leucine were hydrolyzed. Since H are detected in the body fluids, they are likely to act as endogenous competitors of Ang IV.

Domaines: Biochimie [q-bio.BM]

Isabelle Garreau, Dominique Chansel, Sophie Vandermeersch, Ingrid Fruitier, Jean Marie Piot, et al.. Hemorphins inhibit angiotensin IV binding and interact with aminopeptidase N. Peptides, 1998, 19 (8), pp.1339-1348. ⟨10.1016/s0196-9781(98)00075-8⟩. ⟨hal-01967821⟩