Akt phosphorylation of the small arterial segments stimulated by the cyclic transmural pressure after treatments. (A) Expression of Akt phosphorylation. Akt, protein kinase B; p-Akt, phosphorylated Akt. The treatments included the endothelial cells mechanically denuded using a wire (D-ECs), intact and untreated vessel segment (IUT), isovolumic condition (IVC) to maintain diameter constant during the cyclic transmural pressure, GRGDSP peptide incubation (RGD), GRGESP peptide incubation (RGE), incubation with function-blocking integrin α₅β₁ antibody (α₅β₁), and incubation with function-blocking integrin α_vβ₃ antibody (α_vβ₃). *, P < 0.05 versus IVC. Error bars represent mean ± SEM. (B) Immunofluorescence to verify Akt phosphorylation in endothelial cells. Fluorescent secondary antibody (Alexa Fluor 546; red) indicated that the signal of Akt phosphorylation was stronger in endothelial cells than that in the medial layer of both coronary small arteries (CA) and skeletal muscular small arteries (SMA) in IUT, and no difference between endothelial cells and the medial layer in both CA and SMA at IVC, α₅β₁ antibody inhibition, or α_vβ₃ antibody inhibition. Internal elastic lamina was indicated by green and the nucleus by blue.