Abstract 254: Chronic Ang II Hypertension Differentially Impacts the Renal T Cell Profile in Males and Females

Abstract

T cells contribute to angiotensin (Ang) II hypertension in male animal models yet less is known in females. We previously showed that hypertensive female rats have more immuno-suppressive T regulatory cells (Tregs) and males have more pro-inflammatory Th17 cells in their kidneys. This study tested the hypothesis that Ang II results in greater expression of renal Tregs in females and Th17 cells in males. 12 wk old male and female Sprague Dawley rats (SD) were treated with Ang II (200 ng/kg/min) or vehicle for 2 wks; blood pressure (BP) was measured via tail cuff and renal T cell profiles were measured via flow cytometry. Ang II infusion increased BP in both sexes (mmHg: males: 130±2 to 152±2; females: 123±1 to 146±1; p<0.05). Females had lower CD3 + T cell counts at baseline vs. males (p<0.0001). Ang II significantly increased CD3 + T cells in both sexes (p<0.0001). Baseline CD4 + T cell counts were comparable between male and female SD. Ang II infusion increased CD4 + T cells in both sexes (p<0.0001), however, expression remained lower in females (p=0.04). Females had greater expression of Tregs (p<0.0001) at baseline. Ang II infusion increased Treg expression in females (p=0.004), with no effect in males. Males expressed more baseline Th17 cells than females (p<0.001). Though Ang II increased levels in both sexes (p<0.001), females maintained significantly reduced Th17 cell expression vs. males (p<0.001). Therefore, Ang II resulted in female SD having greater renal expression of Tregs and males having greater expression of Th17 cells. In conclusion, sex differences in the T cell profile may contribute to observed sex differences in BP control.