Stimulation of Epithelial Sodium Channels in Endothelial Cells by Bone Morphogenetic Protein-4 Contributes to Salt-Sensitive Hypertension in Rats

Figure 4

HS diet impairs endothelium-dependent relaxation and stimulates ENaC via p38 MAPK in SS rats. (a, b) Upper panels are representative Western blots and summarized data showing p38 MAPK and p-p38 MAPK protein levels under each condition in endothelial cells isolated from SS rats fed NS or HS diet. vs. NS ( for each group). (c) Representative traces of ACh-induced artery relaxation in NS or HS diet-fed SS rats, in absence of or in the presence of 20 μM SB202190 for 4 hours. The first dot in each plot represents the time when Phe (10 μM) was added. The following dots indicate ACh concentrations gradually increased to 0.1 nM, 1 nM, 10 nM, 100 nM, 1 μM, 10 μM, and 100 μM. (d, e) Summaries of relaxation responses of mesenteric arteries to different doses of ACh (d) and to different doses of NTG (e). vs. NS; ^#vs. HS ( for each group). (f) Representative ENaC single-channel currents generated from the intact endothelial cells of mesenteric artery isolated from NS or HS diet-fed SS rats, in the absence of or in the presence of 20 μM SB202190 for 4 hours. (g) Summary of ENaC P_O obtained from single-channel recordings from the SS rats, under indicated conditions, as shown in (f). indicates vs. NS; ^#represents vs. HS ( rats for each group).

(a)

(b)

(c)

(d)

(e)

(f)

(g)