Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Science. 2011 Feb 25;331(6020):1078-80. doi: 10.1126/science.1200708.
Certain fish and amphibians retain a robust capacity for cardiac regeneration throughout life, but the same is not true of the adult mammalian heart. Whether the capacity for cardiac regeneration is absent in mammals or whether it exists and is switched off early after birth has been unclear. We found that the hearts of 1-day-old neonatal mice can regenerate after partial surgical resection, but this capacity is lost by 7 days of age. This regenerative response in 1-day-old mice was characterized by cardiomyocyte proliferation with minimal hypertrophy or fibrosis, thereby distinguishing it from repair processes. Genetic fate mapping indicated that the majority of cardiomyocytes within the regenerated tissue originated from preexisting cardiomyocytes. Echocardiography performed 2 months after surgery revealed that the regenerated ventricular apex had normal systolic function. Thus, for a brief period after birth, the mammalian heart appears to have the capacity to regenerate.
某些鱼类和两栖类动物在整个生命周期中都保持着强大的心脏再生能力，但成年哺乳动物的心脏并非如此。哺乳动物是否缺乏心脏再生能力，或者这种能力是否存在但在出生后早期就被关闭，一直不清楚。我们发现，1 天大的新生小鼠的心脏在部分外科切除后可以再生，但这种能力在 7 天大时就丧失了。1 天大的小鼠的这种再生反应表现为心肌细胞增殖，而很少有肥大或纤维化，从而将其与修复过程区分开来。遗传命运图谱表明，再生组织中的大多数心肌细胞都源自原有心肌细胞。心脏超声检查显示，手术后 2 个月，再生的心室顶部具有正常的收缩功能。因此，在出生后的短暂时间内，哺乳动物的心脏似乎具有再生能力。
