Inhibition of Necrosis Via Necrox‐5 Attenuates The Development Of Hypertension In Male, But Not Female Spontaneously Hypertensive Rats (SHR)

Abstract

It is well established that hypertension is accompanied by cell death, however, less is known regarding the role of cell death in blood pressure (BP) control. Necrosis is an uncontrolled pathologic form of cell death that is associated with inflammation. Therefore, the goal of the current study was to test the hypothesis that necrosis contributes to the development of hypertension in SHR. Initial studies measured renal necrosis in 13 wk old male and female SHR (n=9) using flow cytometry. Male SHR had greater renal necrosis compared to female SHR (3.7±0.4% vs. 0.4±0.2% of total renal cells, respectively; p<0.0001). Additional male and female SHR were then randomized to receive vehicle or Necrox‐5 from 6–12 weeks of age (1 mg/kg via IP injection twice weekly; n=4); Necrox‐5 is a cell permeable inhibitor of necrosis that blocks oxidative stress induced necrotic cell death. BP was measured weekly via tail‐cuff analysis and via carotid catheter at sacrifice. Following 6 wks of treatment, kidneys were isolated and necrosis was measured by flow cytometry. Treatment with Necrox‐5 beginning at 6 wks of age attenuated maturation‐induced increases in BP in male SHR (Necrox‐5: 152±11 vs Control: 177±4 mmHg; p=0.07). BP in female SHR was not altered by chronic Necrox‐5 treatment (Necrox‐5: 152±14 vs. Control: 146±11 mmHg; p=0.72). In addition, the sex difference in BP apparent in control rats was abolished by Necrox‐5 treatment. Consistent with these results, Necrox‐5 treatment for 6 wks decreased renal necrosis only in males (Necrox‐5: 1.5±0.5% vs Control: 3±0% of total renal cells). Taken together, our data suggest that greater cell death in male SHR compared to female SHR contributes to sex differences in BP by exacerbating age‐related increases in BP in males.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.