[Effect of bradkinin-potentiating snake venom peptides and C-terminal pentapeptide fragment of bradkinin on carboxypeptidase N and kiniase activities of human blood serum].
Effects of bradikinin-potentiating peptides (BPP5a and BPPB), which are identical to peptides from Bothrops jararaca and Agkistrodon halys blomhoffii snake venom, and pentapeptide C-terminal bradikinin fragment on carboxypeptidase N and kinase activities in human blood serum are studied. It is found that BPP5a and BPPB at concentrations of 5-10(-4) M and 2.5-10(-4) M respectively do not inhibit the hydrolysis of hippuryl-L-lysine and hippuryl-L-argininic acid by carboxypeptidase N and at a concentration of 2-10(-3) M they do not affect the rate of the release of C-terminal arginine residue from bradikinin. BPP5a and BPPB do not inhibit the kininase activity of diluted human blood serum in vitro. Unlike BPP5a and BPPB, C-terminal pentapeptide bradikinin fragment is a competitive inhibitor of carboxypeptidase N, and it inhibits (at a concentration of 5-10(-4) M) the hydrolysis of hippuryl-L-lysine and hippuryl-L-argininic acid by 50%. It also inhibits the hydrolysis of bradikinin with diluted human blood serum. BPP5a and BPPB have an inconstant constriction effect on isolated rat uterus at concentration exceeding 4-6 orders the concentration of bradikinin. BPP5a at concentrations from 4-10(-9) to 4-10(-8) g/ml increases the sensitivity  of rat uterus in 1.6--2.0 times.
D000818:Animals; D001667:Binding, Competitive; D001681:Biological Assay; D001920:Bradykinin / Q000494:pharmacology*; D002268:Carboxypeptidases / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D001121:Lysine Carboxypeptidase / Q000037:antagonists & inhibitors / Q000097:blood*; D009842:Oligopeptides / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology*; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D051381:Rats; D012910:Snake Venoms / Q000494:pharmacology; D014599:Uterus / Q000187:drug effects
D009842:Oligopeptides; D010446:Peptide Fragments; D010455:Peptides; D012910:Snake Venoms; D002268:Carboxypeptidases; D007703:Peptidyl-Dipeptidase A; D001121:Lysine Carboxypeptidase; D001920:Bradykinin
Vliianie bradikininpotentsiruiushchikh peptidov zmeinogo iada i C-kontsevogo pentapeptidnogo fragmenta bradikinina na aktivnost' karboksipeptidazy N i kininaznuiy aktivnost' syvortki krovi cheloveka