BDNF and its associated tropomyosin-related kinase receptor B (TrkB) nurture vessels and nerves serving the heart. However, the direct effect of BDNF/TrkB signaling on the myocardium is poorly understood. Here we report that cardiac-specific TrkB knockout mice (TrkB-/-) display impaired cardiac contraction and relaxation, showing that BDNF/TrkB signaling acts constitutively to sustain in vivo myocardial performance. BDNF enhances normal cardiomyocyte Ca2+ cycling, contractility, and relaxation via Ca2+/calmodulindependent protein kinase II (CaMKII). Conversely, failing myocytes, which have increased truncated TrkB lacking tyrosine kinase activity and chronically activated CaMKII, are insensitive to BDNF. Thus, BDNF/TrkB signaling represents a previously unidentified pathway by which the peripheral nervous system directly and tonically influences myocardial function in parallel with β-adrenergic control. Deficits in this system are likely additional contributors to acute and chronic cardiac dysfunction. BDNF TrkB receptorcardiac contractility/relaxation CaMKII neurotrophins We are grateful to Dr. David D. Ginty for providing us with TrkBF616A and TrkB conditional knockout mice.
| Identifer | oai:union.ndltd.org:ETSU/oai:dc.etsu.edu:etsu-works-16726 |
| Date | 10 February 2015 |
| Creators | Feng, Ning, Huke, Sabine, Zhua, Guangshuo, Tocchetti, Carlo G., Shi, Sa, Aiba, Takeshi, Kaludercice, Nina, Hoover, Donald B., Beckg, Sarah E., Mankowskig, Joseph L., Tomaselli, Gordon F., Bersh, Donald M., Kassa, David A., Paoloccia, Nazareno |
| Publisher | Digital Commons @ East Tennessee State University |
| Source Sets | East Tennessee State University |
| Detected Language | English |
| Type | text |
| Source | ETSU Faculty Works |
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