Fig. 3.

Altered shear stress gene expression in OFT-banded hearts.

A. An increase of the shear stress responsive genes, KLF2, was detected in the primordial mitral valve endocardial lining of both septal and lateral leaflets (arrows) in banded (b, b’) compared to control hearts (a, a’). In one banded heart (n = 1/7), a noticeable decrease of EDN1 was found in the compact myocardium of the outer curvature of the left ventricle (d, arrowhead in d’) but an increase was found in the right ventricle (d, arrow in d’). In contrast, EDN1 was uniformly expressed in the compact myocardium of both ventricles in controls (c, arrow and arrowhead in c’). Experimental control GAPDH showed ubiquitous expression in both control and banded hearts (e, e’ and f, f’). n = 9 for control and n = 7 for OFT-banded hearts. a’–f’ are the boxed areas in a–f. Scale bar: 300 μm for Aa-f, 150 μm for Aa’–f’. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

B & C. Relative expression of shear stress responsive genes was determined by qPCR in HH29 control and OFT-banded hearts. A significant upregulation of KLF2 was found (1.15 fold) in banded hearts (**P < 0.01) (B). Downregulation of EDN1 by 0.65 fold was found in the OFT-banded hearts (***P < 0.001) (C). Two-tailed Student's t-test; data indicate mean ± s.e.m. (n = 5).