Abstract:
We present the first comparison of the global energetic performance between the heart ex vivo and its tissues in vitro of the diabetic and of the hypertensive rats. Using our unique suite of recently constructed instruments, we varied the metabolic demands of the preparations by challenging them to perform work against an extensive range of afterloads. This manoeuvre, not possible in the in vivo heart, has revealed distinct energetic performance differences between the heart and its tissues, and between diabetes and hypertension. We propose several underlying mechanisms that not only proffer reconciliation of these differences, but also provide deeper insights into cardiac energetics in disease.