Acute superoxide radical scavenging reduces blood pressure but does not influence kidney function in hypertensive rats with postischemic kidney injury.

Abstract

Acute kidney injury (AKI) is associated with significant morbidity and mortality in hypertensive surroundings. We investigated superoxide radical molecules influence on systemic haemodynamic and kidney function in spontaneously hypertensive rats (SHR) with induced postischemic AKI. Experiment was performed in anesthetized adult male SHR. The right kidney was removed, and left renal artery was subjected to ischemia by clamping for 40 minutes. The treated group received synthetic superoxide dismutase mimetic TEMPOL in the femoral vein 5 minutes before, during, and 175 minutes after the period of reperfusion, while the control AKI group received the vehicle via the same route. All parameters were measured 24 h after renal reperfusion. TEMPOL treatment significantly decreased mean arterial pressure and total peripheral resistance (P < 0.05) compared to AKI control. It also increased cardiac output and catalase activity (P < 0.05). Lipid peroxidation and renal vascular resistance were decreased in TEMPOL (P < 0.05). Plasma creatinine and kidney morphological parameters were unchanged among TEMPOL treated and control groups. Our study shows that superoxide radicals participate in haemodynamic control, but acute superoxide scavenging is ineffective in glomerular and tubular improvement, probably due to hypertension-induced strong endothelial dysfunction which neutralizes beneficial effects of O2(-) scavenging.

• Authors: Zoran Miloradović, Milan Ivanov, Nevena Mihailović-Stanojević, Jelica Grujić Milanović, Đurđica Jovović, Una-Jovana Vajić, Jasmina Marković-Lipkovski
• Journal: BioMed research international (Biomed Res Int) Vol. 2014 Pg. 512619 ( 2014) ISSN: 2314-6141 [Electronic] United States
• PMID: 25050356 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cyclic N-Oxides
• Free Radical Scavengers
• Spin Labels
• Superoxides
• tempol

Topics

• Animals
• Blood Pressure (drug effects)
• Cyclic N-Oxides (pharmacology, therapeutic use)
• Free Radical Scavengers
• Heart Rate (drug effects)
• Hemodynamics (drug effects)
• Ischemia (drug therapy, pathology, physiopathology)
• Kidney (blood supply, drug effects, pathology, physiopathology)
• Kidney Function Tests
• Male
• Rats, Inbred SHR
• Regional Blood Flow (drug effects)
• Reperfusion Injury (drug therapy, pathology, physiopathology)
• Spin Labels
• Superoxides (metabolism)
• Vascular Resistance (drug effects)