Effects of Reduced Cyclic Stretch on Vascular Smooth Muscle Cell Function of Pig Carotids Perfused Ex Vivo

Background With advancing age arteries stiffen, reducing arterial compliance and leading to the development of systolic hypertension and to a substantial increase in pulse pressure. An augmented pulse pressure can be a predictor of the development of hypertension, which has been linked to several cardiovascular diseases including atherosclerosis, and to pathologies such as diabetes and renal dysfunction. In this study, we tested the hypothesis that reduced wall compliance induces pulse-pressure-mediated changes in arterial wall metabolism and remodeling. Methods Porcine carotid arteries were perfused for 24 h using an ex vivo arterial support system. Control arteries were exposed to a pulse shear stress (6 ± 3 dynes/cm2) combined with a pulse pressure of 80 ± 10 mm Hg, yielding a physiological cyclic stretch of 4-5%. A reduced compliance group was also studied, in which arteries were wrapped with an external band, thereby decreasing cyclic stretch to levels