Antioxidant and Antiinflammatory Therapies Preserve Renal Autoregulation in 5/6 Nx Rats

Abstract

The aim of this study was to test whether antiinflammatory or antioxidant therapies preserve autoregulation in a model of chronic renal disease (5/6 Nx) We studied the following groups (n=6-7 each): Control sham, 5/6 Nx, 5/6 Nx + mycophenolate mofetil (MMF) and 5/6 Nx+Curcumin (Cur). Daily gavage dosed C (120 mg/k BW) and MMF (30 mg/k BW). Animals were followed during one month and SBP, by tail-cuff, measured. At the end of the study baseline renal blood flow and autoregulation (at fixed BP 100, 130 and 150 mmHg) were evaluated in anesthetized animals. Arterial pressure was 44% higher in 5/6 Nx compared to C. Cur partially prevented HT, while MMF further reduced BP. Absolute RBF was reduced in 5/6 Nx groups by 50% compared to control sham. Despite this effect, renal autoregulatory response to fixed increments in BP was preserved in Cur and MMF treated animals (fig 1). Co-treatment with Cur+MMF did not produce a synergy effect (3 rats). Moreover, acute treatment with TEMPOL to 5/6 Nx rats reduced systemic BP by 30%, however did not restore autoregulatory response, therefore RBF also decreased by 30% in those animals (4 rats) In conclusion, antioxidant and anti-inflammatory therapies preserve renal autoregulation likely inhibiting a common pathogenic pathway since the co-treatment did not provide further benefit. The salutary effect afforded by the two therapies may also be related to the preservation of vascular structure since acute relive of oxidative stress with TEMPOL did not restore autoregulatory response.