Figure 9. Cardiovascular changes in adult homozygous (homo) gene deletion mutants.

(A) Elevated peak blood velocity in the ascending aorta of XS and CH gene trap mutants (solid circles) relative to WT controls (open circles). Group means are indicated by horizontal lines. The lower dashed line shows the mean + 2SD and the upper dashed line the mean + 3SD for WT point mutant controls. 5 of 6 XS, and 4 of 5 CH mice had elevated peak velocities (>2SD relative to WT point mutants). (B) Scanning electron microscopy images of the aortic valve of a WT littermate (left) and a XS homozygote with aortic valvular stenosis (right). Note marked thickening of the valve leaflets of the mutant. (C) Arterial blood pressure by tail cuff plethysmography in XS and CH lines. *** P<0.001. N is shown in the bar. Mean ± SE. Note that significant hypotension was observed in the CH line only. (D) Cross-sectional view of the heart of a WT and CH homozygous mutant. Note the enlarged right ventricle (RV) in the mutant. Prominent RV enlargement was observed in 2 of 7 XS and 6 of 8 CH homozygotes but no WT controls. (E) Doppler velocity waveform in the proximal pulmonary artery in a WT and CH homozygous deletion mutant. Reversed diastolic blood velocities (arrows) indicate pulmonary valve regurgitation (observed in 5 of 7 XS and 8 of 8 CH homozygotes but no WT).