Abstract P171: Comparison Of Modulation Of Renal Arterial Tone By Perivascular Adipose Tissue Between Two Animal Models Of Metabolic Syndrome

Abstract

Sex differences have recently been noticed in the regulation of arterial tone by perivascular adipose tissue (PVAT). In SHRSP.Z- Lepr fa /IzmDmcr (SHRSP.ZF) rats, an animal model of metabolic syndrome (MetS), we demonstrated that mesenteric and renal PVAT in female rats consistently have an enhancing effect on vasodilation at 23 weeks, an age by which the effect of PVAT is impaired in the male rats. This could explain the sex differences in the prevalence of cardiovascular complications in patients with MetS. Therefore, we determined whether the sex difference in PVAT response also occurs in another animal model of MetS, SHR/NDmcr-cp (SHR-cp) rats.Renal arteries were isolated from male and female 23-week-old SHR-cp rats, and ring preparations with and without PVAT were made. After a stable contraction was obtained by phenylephrine administration, vasodilation in response to acetylcholine was examined using organ bath methods.Vasodilation in arteries without PVAT from female rats was smaller than that in arteries without PVAT from male rats, and presence of PVAT in arteries from female rats increased vasodilation to the same level as that observed in arteries without PVAT from male rats. Furthermore, renal PVAT in male rats was shown to have an enhancing effect on vasodilation.The present study did not identify sex differences in renal PVAT-mediated modulation in SHR-cp rats because the enhancing effects of PVAT did not disappear in male SHR-cp rats, in contrast to that observed in male SHRSP.ZF rats at the same age. The difference in PVAT response in male rats between two MetS models may be due to differences in the severity of MetS symptoms, especially blood pressure, between the models.