Figure 5. Cyclic stretch-induced expression of EGFR ligand mRNAs is abrogated by hypercapnia.

Relative quantitation by real-time polymerase chain reaction of mRNAs for HB-EGF, AREG and EREG, demonstrates induction within 30 min by cyclic stretch under normocapnia (5% CO₂) (two-way ANOVA; *P < 0.05 compared to previous time point in same CO₂ condition). This induction is reduced when cells are subjected to stretch under hypercapnia (12% CO₂) (two-way ANOVA; †P < 0.05 vs. normocapnia at same time point; n = 4). AREG, amphiregulin; EREG, epiregulin; HB-EGF, heparin-binding epidermal growth factor-like growth factor.