Ang (angiotensin) 1-7 MasR (Mas receptor) and D2R (dopamine D2 receptor) stimulation is coupled to anti-inflammatory responses. In the present work, we investigated the hypothesis that the anti-inflammatory action mediated by both receptors results from MasR-D2R heteromerization. Human monocyte (THP-1) cells differentiated to macrophages and exposed to lipopolysaccharide were employed. Ang (1-7) and the D2R agonist SUM (sumanirole) induced a decrease in proinflammatory IL (interleukin) 6 release in human macrophages exposed to a proinflammatory stimulus. The Ang (1-7)-induced decrease in IL-6 was blocked by the D2R antagonist. Conversely, the SUM induced decrease in IL-6 was prevented by the MasR antagonist and when MasR expression was downregulated, suggesting MasR-D2R interaction. Co-immunoprecipitation assay in THP-1 cells and in human monocyte differentiated macrophages from peripheral blood mononuclear cells confirmed MasR-D2R interaction. To avoid the influence from other receptors, MasR-D2R interaction was characterized in transfected human embryonic kidney 293T cells. Fluorescence resonance energy transfer analysis showed that MasR and D2R formed a constitutive heteromer, which was not modified by their agonists. Ang (1-7) and dopamine stimulated ERK (extracellular signal-regulated kinase) 1/2 and Akt (protein kinase B) phosphorylation only in cells expressing MasR-D2R heteromers, but not in cells expressing each receptor alone. Ang (1-7)-stimulated ERK1/2 and Akt phosphorylation was prevented by D2R blockade while the effect of dopamine was prevented by MasR blockade, reinforcing the fact that MasR-D2R heteromers are involved in ERK1/2 and Akt activation induced by their agonists. Our findings provide new evidence regarding the mechanisms underlying the cross-talk between the Ang (1-7)/MasR axis and the dopaminergic system in response to a proinflammatory process.

Fil: Rukavina Mikusic, Natalia Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina

Fil: Mazzitelli, Luciana Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina

Fil: Silva, Mauro Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina

Fil: Gironacci, Mariela Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina

Fil: Grecco, Hernan Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina

Fil: Gomez, Karina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina

Fil: Santos, Robson A.S.. Universidade Federal de Minas Gerais; Brasil