Effect of bradykinin on bradykinin-B2 receptor in rat aortic vascular smooth muscle cells and the involved signal transduction pathways

Abstract

The aim of this paper is to study the effect of bradykinin (BK) on bradykinin-B2 receptor as well as the possible involved signal transduction pathways in cultured rat aortic vascular smooth muscle cells (VSMCs). Rat aortic VSMCs were cultured. Cells after 4–6 passages were used in the experiment. VSMCs were incubated with BK, BK+ B2 receptor inhibitor (HOE-140), BK+ MEK inhibitor (PD98059), BK+ mitogen-activated protein kinase (MAPK) inhibitor (apigenin), BK+ phosphoinositide 3-kinase (PI3K) inhibitor (LY294002), and BK+ Akt inhibitor to evaluate the expression of B2 receptor and phosphorylation of signaling molecules MAPK, Akt, and PI3K by Western blot. (1) BK markedly up-regulated the expression of B2 receptor in VSMC. (2) Apigenin, PD98059, Akt inhibitor, and LY294002 inhibited up-regulation of B2 receptor induced by BK. (3) Signal transduction pathways of MAPK and PI3K were involved in the up-regulation of B2 receptor by BK mediation. Results suggest that bradykinin can up-regulate the expression of B2 receptor in VSMCs.

Keywords

bradykinin / vascular smooth muscle cells / signal transduction pathways