title: Potentiation of bradykinin actions by analogues of the bradykinin potentiating nonapeptide BPP9alpha.
abstract: Synthetic analogues of the bradykinin potentiating nonapeptide BPP9alpha indicate significantly different structural requirements for potentiation of the bradykinin (BK)-induced smooth muscle contraction (GPI) and the inhibition of isolated somatic angiotensin I-converting enzyme (ACE). The results disprove the ACE inhibition as the only single mechanism and also the direct interaction of potentiating peptides with the bradykinin receptors in transfected COS-7 cells as molecular mechanism of potentiation. Our results indicate a stimulation of inositol phosphates (IPn) formation independently from the B2 receptor. Furthermore, the results with La3+ support the role of extracellular Ca2+ and its influx through corresponding channels. The missing effect of calyculin on the GPI disproves the role of phosphatases in the potentiating action. These experimental studies should not only contribute to a better understanding of the potentiating mechanisms but also incorporate a shift in the research towards the immune system, in particular towards the immunocompetent polymorphonuclear leukocytes. The chemotaxis of these cells can be potentiated most likely by exclusive inhibition of the enzymatic degradation of bradykinin. Thus the obtained results give evidence that the potentiation of the bradykinin action can occur by different mechanisms, depending on the system and on the applied potentiating factor.
authors.affiliation: Institute of Biochemistry and Biophysics, Biological and Pharmaceutical Faculty, Friedrich-Schiller-University, 07743 Jena, Germany.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Mueller
authors.forename: Rita
authors.initials: R
authors.lastname: Gothe
authors.forename: Wolf-Dieter
authors.initials: WD
authors.lastname: Siems
authors.forename: Gabriele
authors.initials: G
authors.lastname: Vietinghoff
authors.forename: Inge
authors.initials: I
authors.lastname: Paegelow
authors.forename: Siegmund
authors.initials: S
authors.lastname: Reissmann
mesh_terms: D000595:Amino Acid Sequence; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D019556:COS Cells; D002118:Calcium / Q000378:metabolism; D002522:Chlorocebus aethiops; D004357:Drug Synergism; D006168:Guinea Pigs; D006801:Humans; D007295:Inositol Phosphates / Q000096:biosynthesis; D008969:Molecular Sequence Data; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D007703:Peptidyl-Dipeptidase A / Q000187:drug effects; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D043782:Receptor, Bradykinin B2 / Q000819:agonists / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects; D013722:Teprotide / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D007295:Inositol Phosphates; D010455:Peptides; D043782:Receptor, Bradykinin B2; D013722:Teprotide; D010749:Phosphoprotein Phosphatases; D007703:Peptidyl-Dipeptidase A; D001920:Bradykinin; D002118:Calcium