title: Inhibition of human serum oxytocinase (cystine aminopeptidase, E. C. 3.4.11.3) by GnRH peptides.
abstract: The hydrolysis of H-Cys(Bzl)-NH-Meq by human serum oxytocinase (E.C. 3.4.11.3) was inhibited non-competitively by various pyroglutamyl peptides. The most effective were the chicken GnRH II (Ki = 6 x 10(-6) mol l-1) and salmon GnRH (Ki = 12 x 10(-6) mol l-1), while the inhibitory potency of human GnRH was substantially lower (Ki = 60.0 x 10(-6) mol l-1). Variations in inhibitory potency of individual peptides reflected mostly the differences in N-terminal and C-terminal parts of the molecules.
authors.affiliation: Department of Peptide Biochemistry, Czechoslovak Academy of Sciences, Praha.
authors.forename: H P
authors.initials: HP
authors.lastname: Masková
authors.forename: J P
authors.initials: JP
authors.lastname: Burbach
authors.forename: G
authors.initials: G
authors.lastname: Kokotos
authors.forename: C
authors.initials: C
authors.lastname: Tzougraki
authors.forename: T
authors.initials: T
authors.lastname: Barth
mesh_terms: D000595:Amino Acid Sequence; D002855:Chromatography, Thin Layer; D010122:Cystinyl Aminopeptidase / Q000037:antagonists & inhibitors* / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D006868:Hydrolysis / Q000187:drug effects; D008969:Molecular Sequence Data; D011761:Pyrrolidonecarboxylic Acid / Q000494:pharmacology
chemical_list: D007987:Gonadotropin-Releasing Hormone; D010122:Cystinyl Aminopeptidase; D011761:Pyrrolidonecarboxylic Acid