Abstract 214: Exercise Training Attenuates ER Stress in the Kidney Cortex and Improves Renal Function in the Angiotension II-induced Hypertensive Rats

Abstract

Exercise training (ExT) is recommended as an adjuvant to many hypertensive therapies. Recently, we demonstrated that ExT preserves renal structure and function in spontaneously hypertensive rats. However, the mechanism for these beneficial effects of exercise on renal function is not known. In this study, we examined whether ANGII induced ER stress and renal dysfunction in the kidney is attenuated by ExT. Methods: Rats were randomized into sedentary or exercise training (ExT) group. Hypertension was induced by implanting osmotic minipumps containing saline or ANGII 200ng/kg/min for 28 days. At the end of the study animals underwent acute renal clearance study and blood pressure measurements using direct recording. At the conclusion of the study, kidney cortex was examined for ER stress, oxidative stress and renal injury markers using RT-PCR and Western blotting. Results: are tabulated. Protein expression for Grp78 and CHOP were consistent with the RT-PCR data. Studies are underway to determine whether blocking ER stress by itself improves renal function in ANGII infused rats. Conclusions: 1. ANGII induces ER stress and TLR4 in the renal cortex and impairs renal function. 2. ExT attenuates ER stress, inflammation and improves renal function in ANGII induced rats. 3. Disruption of ER function by increased oxidative stress is prevented by ExT a novel pathway for improved renal hemodynamics.