RESUMO
Recently, several studies have reported that respiratory disease may be associated with an increased production of free radicals. In this context, 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) is a free radical-generating compound widely used to mimic the oxidative stress state. We aimed to investigate whether AAPH can generate lung functional, inflammatory, histological and biochemical impairments in the lung. Wistar rats were divided into five groups and instilled with saline solution (714 µL/kg, CTRL group) or different amounts of AAPH (25, 50, 100, and 200 mg/kg, 714 µL/kg, AAPH groups). Seventy-two hours later the animals were anesthetized, paralyzed, intubated and static elastance (Est), viscoelastic component of elastance (ΔE), resistive (ΔP1) and viscoelastic (ΔP2) pressures were measured. Oxidative damage, inflammatory markers and lung morphometry were analyzed. ΔP1 and Est were significantly higher in AAPH100 and AAPH200 than in the other groups. The bronchoconstriction indexes were larger in AAPH groups than in CTRL. The area occupied by collagen and elastic fibers, polymorpho- and mononuclear cells, malondialdehyde and carbonyl groups levels were significantly higher in AAPH200 than in CTRL. In comparison to CTRL, AAPH200 showed significant decrease and increase in the activities of superoxide dismutase and catalase, respectively. AAPH augmented the release of pro-inflammatory cytokines IL-1ß, IL-6 e TNF-α. Hence, exposure to AAPH caused significant inflammatory alterations and redox imbalance accompanied by altered lung mechanics and histology. Furthermore, we disclosed that exposure to AAPH may represent a useful in vivo tool to trigger lung lesions.
RESUMO
OBJECTIVE: The objective of our study was to evaluate the effects of fenoldopam mesylate, a dopamine type 1A receptor agonist and a potent renal vasodilator that markedly increases renal blood flow, on kidney function of patients who were receiving iodinated contrast material for an interventional procedure and thought to be at high risk of contrast-associated nephropathy. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients who received fenoldopam mesylate to determine the acute and, when possible, the longer term effects on kidney function. RESULTS: Twenty-nine cases were reviewed. The average serum creatinine value before contrast administration was 2.55 mg/dL (range, 1.3-5.8 mg/dL) [corrected]. Twenty-four hours after contrast administration, serum creatinine was measured in 28 of the 29 patients. The serum creatinine values had decreased in 16 of the 28 patients by an average of 0.55 mg/dL [corrected]. In nine patients, the serum creatinine value had not changed. Two of the three increases in the serum creatinine value appear to have been caused primarily by problems that did not involve the contrast material. CONCLUSION: The use of fenoldopam mesylate at appropriate doses offers patients at high risk for contrast-associated nephropathy a chance to avoid this complication. To learn the extent and true nature of the effect of fenoldopam mesylate in this patient population requires a rigorous scientific trial, which is currently underway.
