Angiotensin-converting enzyme determn. - based on cleavage of hippuryl peptide substrate

摘要

Determn. of angiotensin-converting enzyme (ACE) activity is effected by contacting an ACE-contg. sample with a synthetic substrate selected from hippuryl-glycyl-glycine and hippuryl-histidyl-leucine, and subjecting the mixt. to foline-Wu treatment or dialysis to provide non-pptd. peptide cleavage prods. e.g., glycyl-glycine to histidyl-leucine in soln. The latter may be determined photometrically after arylation with a nitrobenzene deriv., e.g. trinitrobenzenesulphonic acid or 1-fluoro-2,4-dinitrobenzene. Also claimed is the followinq: the therapeutic and diagnostic use of the inhibition of the activity of ACE present in sperm, seminal fluid, prostate tissue, testicular tissue, corneal tissue, macrophages and monocytes, which may lead to, e.g., the induction, inhibition of blocking of the fertilisation process, degeneration or decompsn. of vasoactive substances, or the tracing and chemical characterisation of disease states in the aforementioned tissues (sic). The ACE assay method uses inexpensive reagents and is suitable for use in clinical laboratories. (Fl).