We used the hybrid ZSF1 [Zucker diabetic fatty (ZDF) spontaneously hypertensive heart failure (ZSF1)] obese rat model that presents with relevant features of clinical HFpEF including – but not limited to – diastolic dysfunction, HF, insulin resistance, hyperglycemia, hypertension, hyperlipidemia, exercise intolerance, etc. While the obese have been reported to have mutations in the leptin receptor [Lepr(fa), Lepr(cp)], the lean counterparts can be heterozygous and may serve as useful controls presenting with hypertension, but without HF or obesity (Schauer et al., 2020; Stolina et al., 2020). The gene discussed is LEPR; the disease is Insulin resistance.