A proliferative burst during preadolescence establishes the final cardiomyocyte number.
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ABSTRACT:
SUBMITTER: Naqvi N
PROVIDER: S-EPMC4078902 | biostudies-literature | 2014 May
REPOSITORIES: biostudies-literature
Publications
A proliferative burst during preadolescence establishes the final cardiomyocyte number.
Naqvi Nawazish N Li Ming M Calvert John W JW Tejada Thor T Lambert Jonathan P JP Wu Jianxin J Kesteven Scott H SH Holman Sara R SR Matsuda Torahiro T Lovelock Joshua D JD Howard Wesley W WW Iismaa Siiri E SE Chan Andrea Y AY Crawford Brian H BH Wagner Mary B MB Martin David I K DI Lefer David J DJ Graham Robert M RM Husain Ahsan A
Cell 20140501 4
It is widely believed that perinatal cardiomyocyte terminal differentiation blocks cytokinesis, thereby causing binucleation and limiting regenerative repair after injury. This suggests that heart growth should occur entirely by cardiomyocyte hypertrophy during preadolescence when, in mice, cardiac mass increases many-fold over a few weeks. Here, we show that a thyroid hormone surge activates the IGF-1/IGF-1-R/Akt pathway on postnatal day 15 and initiates a brief but intense proliferative burst ...[more]
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