A possible increase of activity of endothelial l-arginine/nitric oxide pathway in aortas of diet-induced obesity rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Processo FAPESP: 2009/03771-2

The obesity is associated with cardiovascular disorders. The aim of present purpose was test the hypothesis that the diet-induced obesity is able to generate a vascular adaptive response in aortic rings; this response could be mediated by NO pathway. The present work used Thirty-day-old male Wistar rats (70-100 g) were distributed into two groups: control (C) and obese (Ob). The obesity was induced through of hypercaloric diet during 15 weeks, the vascular response was assessed through different protocols of vascular reactivity studies and characterization of obesity was also evaluated. The obesity was characterized for decreased of glucose tolerance, hyperinsulinemia, hyperleptinemia and rise of adiposity index. In relation to vascular alterations, the diet-induced obesity generated decreased maximal response to noradrenaline, response which was abolished with presence of L-NAME, and increased relaxing to acetylcholine. There was no difference between groups in the blood pressure. The vascular responses observed in present work might have occurred with the aim of decrease of cardiovascular risk linked with obesity pathology; these findings suggest that obesity can be considered a paradoxical disorder.