Cross talk between kinin and angiotensin II receptors in mouse abdominal aorta.
Bradykinin (BK) is a vasorelaxant, algesic and inflammatory agent. Angiotensin II (AngII) is known to control vascular tone and promote growth, inflammation and artherogenesis. There is evidence for cross talking between BK and AngII receptors. Therefore, the effect of lack of kinin receptors was assessed in mice with genetic disruption of B(1) or B(2) and both receptors. Responsiveness of abdominal aortic rings to BK and AngII as well as the receptor gene expression of both peptides were analysed. Although no specific phenotype was displayed in the normotensive and healthy mice lacking the kinin receptors, a decreased expression level of the remaining kinin receptor mRNA was observed. AT(1) receptor mRNA level was also reduced, indicating that kinin receptors regulate AngII receptors. Downregulation of the receptors was well correlated with reduction in the reactivity of both agonists to induce contraction of aortic rings, but other signal regulations must be sought in these transgenic mice. We conclude that cross talk between kinin and AngII receptors occurs in mouse abdominal aorta and that both peptides may regulate the initiation and progression of important pathophysiological processes, such as hypertension and inflammation.
Rodrigues
Eliete S
ES
Department of Biophysics, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, Brazil.
Martin
Renan P
RP
Felipe
Sandra A
SA
Bader
Michael
M
Oliveira
Suzana M
SM
Shimuta
Suma I
SI
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001012:Aorta, Abdominal / Q000187:drug effects / Q000378:metabolism*; D001920:Bradykinin / Q000494:pharmacology; D007093:Imidazoles / Q000037:antagonists & inhibitors; D007705:Kinins / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011725:Pyridines / Q000037:antagonists & inhibitors; D043783:Receptor, Bradykinin B1 / Q000235:genetics / Q000378:metabolism; D043782:Receptor, Bradykinin B2 / Q000235:genetics / Q000378:metabolism; D011945:Receptors, Angiotensin / Q000235:genetics / Q000378:metabolism*; D014665:Vasodilator Agents / Q000494:pharmacology
D007093:Imidazoles; D007705:Kinins; D011725:Pyridines; D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D011945:Receptors, Angiotensin; D014665:Vasodilator Agents; D000804:Angiotensin II; C073402:PD 123319; D001920:Bradykinin; D019331:NG-Nitroarginine Methyl Ester