Endothelin-1 regulates cardiac sympathetic innervation in the rodent heart by controlling nerve growth factor expression
Masaki Ieda, … , Howard J. Federoff, Satoshi Ogawa
Masaki Ieda, … , Howard J. Federoff, Satoshi Ogawa
Published March 15, 2004
Citation Information: J Clin Invest. 2004;113(6):876-884. https://doi.org/10.1172/JCI19480.
View: Text | PDF
Article Cardiology

Endothelin-1 regulates cardiac sympathetic innervation in the rodent heart by controlling nerve growth factor expression

Abstract

The cardiac sympathetic nerve plays an important role in regulating cardiac function, and nerve growth factor (NGF) contributes to its development and maintenance. However, little is known about the molecular mechanisms that regulate NGF expression and sympathetic innervation of the heart. In an effort to identify regulators of NGF in cardiomyocytes, we found that endothelin-1 specifically upregulated NGF expression in primary cultured cardiomyocytes. Endothelin-1–induced NGF augmentation was mediated by the endothelin-A receptor, Giβγ, PKC, the Src family, EGFR, extracellular signal–regulated kinase, p38MAPK, activator protein-1, and the CCAAT/enhancer-binding protein δ element. Either conditioned medium or coculture with endothelin-1–stimulated cardiomyocytes caused NGF-mediated PC12 cell differentiation. NGF expression, cardiac sympathetic innervation, and norepinephrine concentration were specifically reduced in endothelin-1–deficient mouse hearts, but not in angiotensinogen-deficient mice. In endothelin-1–deficient mice the sympathetic stellate ganglia exhibited excess apoptosis and displayed loss of neurons at the late embryonic stage. Furthermore, cardiac-specific overexpression of NGF in endothelin-1–deficient mice overcame the reduced sympathetic innervation and loss of stellate ganglia neurons. These findings indicate that endothelin-1 regulates NGF expression in cardiomyocytes and plays a critical role in sympathetic innervation of the heart.

Authors

Masaki Ieda, Keiichi Fukuda, Yasuyo Hisaka, Kensuke Kimura, Haruko Kawaguchi, Jun Fujita, Kouji Shimoda, Eiko Takeshita, Hideyuki Okano, Yukiko Kurihara, Hiroki Kurihara, Junji Ishida, Akiyoshi Fukamizu, Howard J. Federoff, Satoshi Ogawa

×

Figure 1

Options: View larger image (or click on image) Download as PowerPoint
Specific augmentation of NGF expression by ET-1 in cardiomyocytes. (A) G...
Specific augmentation of NGF expression by ET-1 in cardiomyocytes. (A) Gene expression of four NGF alternatively spliced transcripts (a–d) in murine heart (H), brain (BR), and submaxillary gland (S) was determined by RT-PCR. The number of PCR cycles is 35. m, marker. (B) Cardiomyocytes were stimulated with ET-1, angiotensin II (Ang II), phenylephrine (PE), LIF, or IGF-1 for 2 hours. Northern blot analysis for NGF was performed. (C) Stimulation of cardiomyocytes with ET-1 for specified time intervals. (D) Stimulation of cardiomyocytes with various concentrations of ET-1. (E) Cardiomyocytes were pretreated with BQ123 (BQ) or TAK044 (TAK) for 30 minutes; then RNA was isolated 2 hours after ET-1 stimulation. (F) Induction of NGF expression by ET-1 in cardiomyocytes (CM), but not in cardiac fibroblasts (CF). Results similar to those shown in A–F were obtained in four separate experiments. (G) NGF protein levels in conditioned medium. Augmentation of NGF protein was inhibited by pretreatment with BQ123. (n = 4.) (H) Secretion of NGF by cardiomyocytes was not induced by angiotensin II, phenylephrine, LIF, or IGF-1 (n = 4). *P < 0.001. NS, not significant vs. control.