EDN1 and cardiac hypertrophy: The experiments were designed, with a fairly narrow focus, specifically, to demonstrate the efficacy of a simple, well-established, and inexpensive in vitro model of cardiac hypertrophy as a major investigative tool for more comprehensive studies—with the corollary benefit for adding insight to effects of ET-1 and β-E on HO-1 expression, which will have direct value to both researchers and healthcare providers, who use activity of this enzyme as a lab biomarker and clinical correlate of cardiac symptoms.