Abstract P226: Sex-Dependent Effects of Perivascular Adipose Tissue on Arterial Stiffness in Hypertensive

Abstract

Dillon McClintock, Department of Mechanical Engineering, Michigan State University, East Lansing, MI Sydney Bush, Department of Mechanical Engineering, Michigan State University, East Lansing, MI Lisa Sather, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI Nathan Tykocki, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI Adam Lauver, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI Stephanie W Watts, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI Sara Roccabianca, Department of Mechanical Engineering, Michigan State University, East Lansing, MI Perivascular adipose tissue (PVAT) plays a crucial role in arterial mechanics by significantly reducing arterial stiffness in the thoracic aorta in normotensive rats. This study aims to test the hypothesis that impact of PVAT on arterial stiffness is sex-dependent in an adiposity-driven hypertension rat model. Thoracic aorta from male and female Dahl Salt-Sensitive rats were fed control (10% fat-CD) and high-fat (60% fat-HFD) diets over 16 weeks. Uniaxial mechanical tests were then conducted on aorta samples with PVAT (+PVAT) and without PVAT (-PVAT). In -PVAT samples, arterial wall stiffness at 20% stretch (mimicking in vivo conditions), was higher in males compared to females on a HFD but not on a CD. HFD rats also had higher systolic blood pressures, but the increase was significant only in females. +PVAT samples’ stiffness was reduced by a 95% factor in all groups as compared to -PVAT samples. Furthermore, when including PVAT, the sex difference in the HF diet group was absent. These results suggest that PVAT has a beneficial effect that is preserved in this adiposity-driven hypertension animal model after 16 weeks on diet. Furthermore, remodeling of the arterial wall is more pronounced in male versus female rats and the inclusion of PVAT dampens this sex difference.