Endothelin-1 regulates cardiac sympathetic innervation in the rodent heart by controlling nerve growth factor expression
J. Clin. Invest. Masaki Ieda, et al. 113:876 doi:10.1172/JCI19480 [Go to this article.]

Figure 1
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.