Co-identity of brain angiotensin converting enzyme with a membrane bound dipeptidyl carboxypeptidase inactivating Met-enkephalin

doi:10.1016/0006-291X(79)91718-2

Biochemical and Biophysical Research Communications

Volume 88, Issue 1, 14 May 1979, Pages 215-221

https://doi.org/10.1016/0006-291X(79)91718-2 Get rights and content

Abstract

The distribution in rat brain of angiotensin converting enzyme (EC3.4.15.1) using hippuryl-His-Leu as substrate was identical to a dipeptidyl carboxypeptidase present in membranes assayed with Met-enkephalin as substrate. Highest activity occurred in pituitary, followed by cerebellum, corpus striatum, midbrain, pons-medulla, hypothalamus, cerebral cortex and spinal cord. The ratio of products His-Leu/Tyr-Gly-Gly was identical for all regions but differed from His-Leu/Tyr. Angiotensin converting enzyme purified by immunoaffinity chromatography gave a K_m for hippuryl-His-Leu of 0.5mM and for Met-enkephalin of 0.1 mM. In the presence of the specific inhibitor of angiotensin converting enzyme, SQ 14,225, the Ki value was 10⁻⁷M. Present data point to the co-identity of brain angiotensin converting enzyme with the dipeptidyl carboxypeptidase inactivating enkephalin.

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Co-identity of brain angiotensin converting enzyme with a membrane bound dipeptidyl carboxypeptidase inactivating Met-enkephalin

Abstract

Biochem. Pharmacol

J. Biol. Chem

J. Biol. Chem

J. Biol. Chem

Life Sciences

Nature

J. Biochem. (Japan)

Biochim. Biophys. Acta