Fig. 4.

Western blot analyses of endothelial lysates performed on day 7 demonstrating the effects of ALK5 inhibition on endothelial cell function. A: increased dietary salt intake increased phospho-ALK5 (Ser¹⁶⁵) in the endothelium. Treatment with SB reduced phospho-ALK5 (Ser¹⁶⁵) to levels observed in LS-treated rats. The graph represents a summary of the findings. B: HS diet increased Smad2 phosphorylation by ∼2-fold compared with the LS group, and ALK5 inhibition prevented the salt-induced increases in Smad2 phosphorylation. The graph represents a summary of the findings. C: Western blots using endothelial lysates from rats on day 7 of the study showed that NADPH oxidase (NOX)4 levels increased specifically in the endothelium of rats on the HS diet. The graph represents a summary of the findings. The band at ∼80 kDa is also NOX4 (14) but was not included in the quantified results shown in the graph. ALK5 inhibition completely abolished this salt-induced response. D: the cartoon depicts a summary of the Western blot data. All data are presented as means ± SE; n = 4 rats/group. *P < 0.05 vs. LS, LS SB, and HS SB groups.