Therefore it was reported that spontaneous interaction of B1R and B2R increases the ability of B1R but not of B2R

to be stimulated by its agonist [11]; heterodimerization between B2R and AT1R causes increased activation of G protein signaling triggered Nintedanib mw by AT1R but not by B2R [1]; AngII may regulate the expression of B2R mRNA [32], that B2R gene is a downstream target of AngII AT1R [29]; the activity of angiotensin converting enzyme (ACE) is enhanced in kinin B1R knockout mice (B1KO) [20] and by an interaction between ACE and kinin B2R [27]. These data from the literature about cross-talk between RAS and KKS and the evidence for expression of AngII AT1R protein and mRNA in endothelial cells [18], [22], [23], [31] and [35] provide rationale for studying the interactions between AngII and BK receptors in addition to the assessment about vascular reactivity of the kinin as well as the expression level of B2R in the aorta

isolated from transgenic (TGR(Tie2B1)) rats. Experiments were carried out using 300–350 g Sprague-Dawley rats as control (WT) and overexpressing B1R (TGR(Tie2B1)), [17] from the “Centro de Desenvolvimento de Modelos Experimentais” (CEDEME) of the Universidade Federal learn more de São Paulo (UNIFESP). The animals were maintained on standard rat chow at 21–23 °C and kept on 12 h light: 12 h dark cycle and allowed ad libitum access to food and water. The protocols used in this study were in accordance with current guidelines for the care of laboratory animals and ethical guidelines for investigations approved by the Animal Care Committee of UNIFESP. Thoracic aorta were isolated from rat, cleared of connective tissue and mounted as ring preparations into 5 ml organ baths. The rings of aorta were bathed in carboxygenated (95% O2/5% CO2), and modified Krebs-Ringer solution: 144 mM NaCl, 5 mM KCl, 1.1 mM MgSO4, 25 mM NaHCO3, Selleckchem Rucaparib 1.1 mM NaH2PO4, 1.25 mM CaCl and 5.5 mM glucose at 37 °C (pH 7.4). Resting tension was maintained at 0.5 g and the tissues were left to equilibrate for 90 min, with frequent changing of

bathing solution. The tissue viability was assessed with a priming dose of 80 mM KCl and 1 μM norepinephrine (NE), as described previously by [30]. Following a 90 min washout and recovery period, changes in tension produced by the stimulants were measured with an isometric transducer TRI201 (Panlab s.l., Cornella, Barcelona, Spain) through an amplifier Powerlab 4/30 and software Labchart Pro V7 (ADInstruments, Colorado Springs, CO, USA). Cumulative concentration–response curves were constructed for BK applying increasing concentrations (0.1 nM to 1 μM) of the agonist. On the other hand non-cumulative concentration–response curves were obtained for AngI and Ang II to avoid desensitization, as described previously by [3].