Heart regeneration in Astyanax mexicanus

While Astyanax mexicanus surface fish regenerate their heart after injury, their Pachón cave-dwelling counterparts cannot and form a permanent fibrotic scar. To identify differences in gene expression after cardiac injury between the two fish, we performed RNA sequencing. Surface fish and Pachón hearts were isolated at 3, 7 and 14 days post ventricular resection. For sham surgery, the thorax and pericardial sac were opened, but the heart was not injured and the heart was isolated 3 days later.