Fig. 4.
A slower progression of heart failure in binary versus CSQ hearts by echocardiography. Two-dimensional-directed M mode echocardiography was carried out as described in methods. Representative M mode echocardiography was shown for hearts from WT, P2X4R Tg, CSQ Tg, and binary Tg mice at the indicated ages. WT and P2X4R Tg hearts showed similar fractional shortening (FS) and left ventricular (LV) dimensions, whereas the CSQ and binary hearts exhibited a progressive decline of FS and LV chamber dilatation. However, the binary hearts showed a slower heart failure progression such that 8-wk-old (8W) binary hearts had better contractile function with less LV dilatation than 8W CSQ hearts. Similar data were obtained in the 12W binary versus 12W CSQ comparison. 12W binary hearts showed similar FS and LV dilatation as the 8W CSQ hearts. By 16 wk (16W), the binary heart function declined and became similar to that of the 12W CSQ heart.