Myocyte interstitial fibrosis with age.

<p>Representative images of the left ventricle myocardium of 2 mo old WT (<b>A</b>), 1 yr old WT (<b>B</b>), 2 yr old WT (<b>C</b>), and 2 mo old D3KO mice (<b>D</b>). Images show increased content and thickness of fibrillar collagen with age (arrows) in WT hearts and in young D3KO hearts.