PTHLH and heart failure: For example, increased expression and activity of PTHrP-PTH1R have been described in ischemic human ventricular cardiomyocytes and in cardiac samples obtained from patients with heart failure [13,35], and an augmented contractile response to exogenous administration of PTHrP has been reported in porcine myocardium (and isolated porcine cardiomyocytes) following relief of a brief ischemic episode [31].