Metabolism of angiotensins by head membranes of the leech Theromyzon tessulatum

FEBS Letters

Salzet, Michel¹  Laurent, Virginie¹ 

[1] Centre de Biologie Cellulaire, Laboratoire de Phylogénie Moléculaire des Annélides, EA DRED 1027, Groupe de Neuroendocrinologie des Hirudinées, SN3, Université des Sciences et Technologies de Lille, F-59655 Villeneuve d'Ascq Cedex, France

关键词: Angiotensin;    Leech;    Peptidase;    Metabolism;    Membrane;    AI;    angiotensin I;    AII;    angiotensin II;    AII-amide;    angiotensin II-amide;    a-AI;    anti-angiotensin I;    ACE;    angiotensin-converting enzyme;    AP;    aminopeptidase;    DIA;    dot immunobinding assay;    HPLC;    high performance liquid chromatography;    NEP;    endopeptidase-24.11;    RAS;    renin-angiotensin system;    TBS;    Tris/HCl buffer saline;    NAP;    neutral aminopeptidase;    DPAP;    dipeptidyl aminopeptidase;    Arg-AP;    arginyl-aminopeptidase;    Asp-AP;    asparagyl-aminopeptidase;   

DOI  :  10.1016/0014-5793(96)00293-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Angiotensins (angiotensin I, angiotensin II, angiotensin II-amide) have been isolated in leeches and such peptides are involved in diuresis in these animals. To explore possible inactivation mechanisms of these peptides, angiotensins were incubated with head membranes of the leech T. tessulatum. Membranes derived from head parts of this leech are very rich in peptidases. They contain endopeptidase-24.11-like enzyme (NEP-like) associated with a battery of exopeptidase. The way that angiotensins are degraded by the combined attack of these membrane peptidases has been investigated. The contribution of individual peptidases was assessed by adding inhibitors (phosphoramidon, captopril and amastatin) to the membrane fractions, when they were incubated with the peptides. In the case of angiotensin I, the primary attack was performed by a combined action of the NEP-like and the ACE-like enzymes, followed by aminopeptidase attacks. Angiotensin II and III were hydrolyzed by NEP-like enzyme at the same Tyr-Ile bond, whereas the N-terminal arginine residue of angiotensin III was removed by an arginyl aminopeptidase. These results show that angiotensins are efficiently degraded by membranes and that NEP-like enzyme plays a key role in this process.

【 授权许可】

Unknown