A liquid chromatography-assisted assay for angiotensin-converting enzyme (peptidyl dipeptidase) in serum.

An improved fluorometric assay of rat serum and plasma converting enzyme.

The most sensitive nonradiometric routine assay for angiotensin-converting enzyme (ACE) activity uses fluorometry to detect His-Leu released from Hip-His-Leu. Our results indicate that, in contrast to human serum, rat serum and plasma contain large and variable amounts of dipeptidase activity that lead to a subestimation of the ACE activity measured in 0.1 M potassium phosphate buffer, pH 8.3, ...

A rapid assay for angiotensin-converting enzyme activity using ultra-performance liquid chromatography-mass spectrometry.

Angiotensin-converting enzyme (ACE) plays an important role in the renin-angiotensin system and ACE activity is usually assayed in vitro by monitoring the transformation from a substrate to the product catalyzed by ACE. A rapid and sensitive analysis method or ACE activity by quantifying simultaneously the substrate hippuryl-histidyl-leucine and its product hippuric acid using an ultra-performa...

A human lung mast cell chymotrypsin-like enzyme. Identification and partial characterization.

We have used a high performance liquid chromatography assay, which detects chymotryptic cleavage of the phe8-his9 bond of angiotensin I to yield angiotensin II, in order to examine human lung mast cells for the presence of chymotryptic activity. Mast cells, purified from human lung by enzymatic dispersion, countercurrent elutriation, and Percoll gradient centrifugation, were lysed or challenged...

Inhibition of human peptidyl dipeptidase (angiotensin I converting enzyme: kininase II) by human serum albumin and its fragments.

Purified peptidyl dipeptidase (angiotensin I converting enzyme or kininase II) from human lung or hog kidney is inhibited by commercially prepared plasma protein preparations, by human serum albumin and by the additive albumin stabilizer, acetyltryptophan. After the initial steps of purification, albumin was detected by immunodiffusion as a component in human lung peptidyl dipeptidase preparati...

Serum angiotensin converting enzyme levels in AIDS.