The present study addressed the effect of interventions aimed to increase NO in the setting of acute renal ischemia/reperfusion (I/R) in uninephrectomized rabbits. In the 60-minute post-I/R period, L-arginine+superoxide (O2.-) dismutase (SOD) synergistically improved the renal functional (69.
View Article and Find Full Text PDFThe present study addressed the acute effects of endothelin-1 on renal function and neutrophils accumulation in the setting of in vivo severe (60 min) acute ischemia/reperfusion. Ischemia/reperfusion decreased renal functional parameters and increased renal neutrophil accumulation and medullary congestion. All these parameters markedly improved with the intrarenal administration of anti-endothelin-1 antiserum.
View Article and Find Full Text PDFBackground: In recent studies, it has been hypothesized that the protective anti-ischemic effects of aspirin outweigh the effects of inhibition of platelet thromboxane A2 synthesis. Recently, we have found that the antiaggregating effects of aspirin significantly affect nitric oxide (NO) generation by neutrophils.
Methods And Results: The present study used circulating neutrophils from myocardial ischemic rabbits to assess the effect of aspirin on the circulating neutrophil-derived NO production and, subsequently, on the modulation of platelet activation.
Background: Based on recent evidence showing that endothelin-1 stimulates several activation mechanisms on neutrophils, the aim of the present study was to analyze the effects of endothelin-1 on neutrophil adhesion to endothelial cells and neutrophil accumulation in the heart.
Methods And Results: The experiments included (1) adhesion of 51Cr-labeled human neutrophils to bovine endothelial cells in culture both in the presence and absence of monoclonal antibodies against the alpha- and beta-subunits of integrins; (2) surface expression of the alpha- and beta-integrin antigens; (3) accumulation of 51Cr-labeled neutrophils on the isolated perfused rabbit heart; (4) in vivo accumulation of autologous neutrophils in the heart, as assessed by myeloperoxidase activity. Endothelin-1 stimulated neutrophil adhesion to endothelial cells (increase of 1 x 10(5) +/- 1 x 10(4) neutrophils per well).
The present study examined the mechanisms of the renal effect of the NO-donor aminoacid, L-Arg and different non-NO-donor aminoacids, namely L-Asn, L-Ala, L-Gly L-Gln administered separately. In conscious, unrestricted Wistar rats, a bolus of L-Arg produced a short-lasting decrease in mean arterial pressure. No variations in mean arterial pressure were found with either L-Gly, L-Asn, L-Ala or L-Gln.
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