Figure 11.

Inhibition of Orai1 Ca²⁺ channel prevented TGF-β1–induced smad2/3 phosphorylation in HK2 cells. (A) Representative immunoblotting and corresponding semiquantification of phosphorylated smad2/3 and smad2/3 protein abundance in response to TGF‑β1 treatment in HK2 cells. Knockdown of Orai1 by shRNA significantly suppressed phosphorylation of total smad2/3 induced by TGF‑β1. Values are mean±SEM, n=6. ^#P≤0.05 or ^##P≤0.01 versus TGF‑β1+Ad‑lacz–shRNA. (B) Representative immunoblotting and corresponding semiquantification of phosphorylated smad2/3 and total smad2/3 protein abundance in response to TGF‑β1 in HK2 cells. Treatment with SOC channel blocker SKF96365 or IP3 receptor antagonist 2-APB inhibited smad2/3 phosphorylation induced by TGF‑β1. Values are mean±SEM, n=6. ^##P≤0.01 versus TGF‑β1+DMSO. (C, D) Representative immunoblotting and corresponding semiquantification of phosphorylated smad2/3 and smad2/3 protein, fibronectin, and collagen IV abundance in response to TGF‑β1 in HK2 cells. Calcineurin inhibitor FK‑506 (10 µmol/L) but not CaMK II inhibitor KN‑93 (10 µmol/L) decreased phosphorylation of smad2/3 and expression of fibronectin and collagen IV induced by TGF‑β1. Values are mean±SEM, n=5. **P<0.01 versus nontreated group; ^#P<0.05 or ^##P≤0.01 versus TGF‑β1+DMSO.