RESUMO
We have investigated the ability of serum from uremic patients to modify the thrombogenic properties of the endothelium. The effect of the uremic media on the morphology of ECs, and their resistance to flow was analyzed. The reactivity of the extracellular matrix (ECM) generated by ECs towards normal platelets was evaluated in a parallel-plate perfusion chamber. Exposure of ECs to uremic media resulted in abnormal morphology and signs of accelerated growth. Detachment of ECs exposed to circulating blood was increased when cells had been grown with media supplemented with uremic serum (22% vs 13%). Platelet deposition and formation of aggregates were significantly elevated on ECMs generated in the presence of uremic media (40.23 +/- 6.43% vs 25.42 +/- 2.69%, p < 0.05, n = 5). Immunocytochemical methods detected an enhanced expression of von Willebrand factor antigen on uremic ECMs (uremic 17.1 +/- 4.2% vs control 13.57 +/- 3.98%, p < 0.05) and its mRNA expression in endothelial cells (uremic 213.24 +/- 6.13 vs control 200.77 +/- 7.52, p < 0.05). These results suggest that uremic medium alters endothelial function and impairs the antithrombotic functions of cultured endothelial cells. This effect may contribute to the increased cardiovascular and thrombotic risk reported in ESRD patients.
Assuntos
Endotélio/citologia , Fator de von Willebrand/biossíntese , Células Cultivadas , Meios de Cultura , Matriz Extracelular/química , Hemostasia , Humanos , RNA Mensageiro/análise , Ácido Úrico , Fator de von Willebrand/análise , Fator de von Willebrand/genéticaRESUMO
The effect of a fish oil enriched diet containing about 3 g of eicosapentaenoic acid was studied in 10 patients with aspirin intolerant asthma. Subjects were studied during six weeks on a control diet followed by six weeks on the fish oil diet in a single blind study design. They were asked to record their peak expiratory flow (PEF) twice daily, bronchodilator and steroid doses, and subjective ratings of pulmonary symptoms on diary cards. There were no significant changes in symptom scores over the six weeks of either the control diet or the fish oil diet. PEF values, however, were significantly lower during the fifth and sixth week of the fish oil diet than during the control diet (308 v 262 l/min week 5 and 306 v 256 l/min week 6). Bronchodilator usage was also greater during the fifth and sixth week of the fish oil diet than during the control period (12.0 v 7.4 and 13.0 v 7.4 puffs a day in weeks 5 and 6). This pilot study suggests that fish diets may have a deleterious effect on patients with aspirin intolerant asthma.