Biphasic Effect of Bradykinin on Rabbit Afferent Arterioles

• DOI: 10.1161/01.hyp.32.2.287
• Publication Date: 2012-06-12T00:53:46Z
• Authors: Hong Yu; Oscar A. Carretero; Luis A. Juncos; Jeffrey L. Garvin
• Keywords: Icatibant; Afferent arterioles; Bradykinin receptor; Arteriole

Abstract —Bradykinin plays an important role in the regulation of renal hemodynamics. However, there have been few studies effect bradykinin on isolated afferent arterioles, vascular segments that are for blood flow and glomerular filtration rate. Our purpose was to study (1) effects perfused rabbit arterioles (2) mechanisms actions. Afferent dissected from rabbits were vitro at 60 mm Hg. In preconstricted with phenylephrine, 10 −12 −10 mol/L increased luminal diameter 9.0±1.0 14.3±1.2 μm ( P <0.003). contrast, −9 −8 decreased 10.8±1.4 9.7±1.2 μm, respectively <0.001). Bradykinin added bath had no arterioles. The addition [des-Arg 9 ]-bradykinin (10 mol/L), a B 1 receptor agonist, lumen 6.7±1.2 <0.002). Icatibant (Hoe 140), 2 antagonist, blocked both vasodilation vasoconstriction induced by as well ]-bradykinin. L-NAME bradykinin-induced dilation or constriction. Indomethacin constriction bradykinin. fact, presence indomethacin, 6.2±0.7 10.7±0.6 <0.001), which attenuated L-NAME. Finally, SQ29548, prostaglandin H /thromboxane A caused all concentrations tested. conclusion, has biphasic Both may be mediated receptors. due cyclooxygenase products, not nitric oxide.