title: In vitro stability of the inhibition of serum converting enzyme by fosinopril.
abstract: With captopril, it has been shown that an erroneous measurement of serum angiotensin converting enzyme (ACE) can be induced by the dissociation of the inhibitor-ACE complex during long-term storage. We have studied the possible dissociation of the fosinopril-ACE complex during the storage of serum samples from healthy male volunteers given a single dose of fosinopril. Serum samples were collected from 5 volunteers, 5 min before, then 4 and 24 h after a unique oral dose of 10 mg fosinopril. ACE activity was measured by a colorimetric and a fluorimetric assay during the hour following the sampling (day 0) and after 21 or 61 days of storage at -20 or -196 degrees C. The degree of ACE inhibition measured in vitro in fresh serum samples differed according to the technique used. Fosinopril has a long-lasting effect with 80% inhibition 24 hours after drug administration. Storage at -20 and -196 degrees C induced a significant decrease in the degree of inhibition measured with the colorimetric method. With the fluorimetric method, a decrease in ACE inhibition was only observed after storage at -20 degrees C but not at -196 degrees C.
authors.affiliation: Institut de Pharmacologie, URA DO 589 CNRS, Université Louis Pasteur, Strasbourg, France.
authors.forename: M
authors.initials: M
authors.lastname: Grima
authors.forename: M
authors.initials: M
authors.lastname: Barthelmebs
authors.forename: D
authors.initials: D
authors.lastname: Stephan
authors.forename: M
authors.initials: M
authors.lastname: Welsch
authors.forename: J L
authors.initials: JL
authors.lastname: Imbs
mesh_terms: D000284:Administration, Oral; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D003124:Colorimetry; D005470:Fluorometry; D017328:Fosinopril; D006801:Humans; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D011392:Proline / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D011392:Proline; D007703:Peptidyl-Dipeptidase A; D017328:Fosinopril