Cardiomyocyte ErbB4 Receptors are Essential for Developmental Hypertrophy and Growth in Neonatal Mice and Maintenance of Cardiac Function in Adult Hearts

Activation of ErbB4 by neuregulin 1 (NRG1) promotes cardiomyocyte hypertrophy and proliferation in mice, while deletion of ErbB4 from cardiomyocytes mid-gestation results in development of dilated cardiomyopathy and reduced survival. However, the role of ErbB4 in the heart after maturation remained unknown. Thus, we deleted ErbB4 in αMHC-MerCreMer (cCre Tg+/)/ErbB4 homozygote floxed (ErbB4 fl/fl) mice at ∼2 months of age with 10 injections of Tamoxifen (20mg/kg/day). Contractile function was reduced in vivo (echocardiography, 16%) and ex vivo (isolated-perfused, 33%) 3 months after gene deletion, while survival in mice up to 8 months after tamoxifen treatment was not modified.
Source: Heart, Lung and Circulation - Category: Cardiology Authors: Tags: 070 Source Type: research