Lopes Patrícia das Dores, de Assis Naiara, de Araújo Natália Ferreira, Moreno Olga Lúcia Maquilon, Jorge Karina Talita de Oliveira Santana, E Castor Marina Gomes Miranda, Teixeira Mauro Martins, Soriani Frederico Marianetti, Capettini Luciano Dos Santos Aggum, Bonaventura Daniella, Cau Stefany Bruno de Assis
Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, MG, Brazil.
Department of Genetics, Ecology & Evolution, Institute of Biological Sciences, Federal University of Minas Gerais, MG, Brazil.
Peptides. 2022 Nov;157:170863. doi: 10.1016/j.peptides.2022.170863. Epub 2022 Aug 24.
Vascular dysfunction induced by angiotensin-II can result from direct effects on vascular and inflammatory cells and indirect hemodynamic effects. Using isolated and functional cultured aortas, we aimed to identify the effects of angiotensin-II on cyclooxygenase (COX) and inducible nitric oxide synthase (iNOS) and evaluate their impact on vascular reactivity. Aortic rings from mice were incubated overnight in culture medium containing angiotensin-II (100 nmol/L) or vehicle to induce vascular disfunction. Vascular reactivity of cultured arteries was evaluated in a bath chamber. Immunofluorescence staining for COX-1 and COX-2 was performed. Nitric oxide (NO) formation was approached by the levels of nitrite, a NO end product, and using a fluorescent probe (DAF). Oxidative and nitrosative stress were determined by DHE fluorescence and nitrotyrosine staining, respectively. Arteries cultured with angiotensin-II showed impairment of endothelium-dependent relaxation, which was reversed by the AT receptor antagonist. Inhibition of COX and iNOS restored vascular relaxation, suggesting a common pathway in which angiotensin-II triggers COX and iNOS, leading to vasoconstrictor receptors activation. Moreover, using selective antagonists, TP and EP were identified as the receptors involved in this response. Endothelium-dependent contractions of angiotensin-II-cultured aortas were blunted by ibuprofen, and increased COX-2 immunostaining was found in the arteries, indicating endothelium release of vasoconstrictor prostanoids. Angiotensin-II induced increased reactive oxygen species and NO production. An iNOS inhibitor prevented NO enhancement and nitrotyrosine accumulation in arteries stimulated with angiotensin-II. These results confirm that angiotensin-II causes vascular inflammation that culminates in endothelial dysfunction in an iNOS and COX codependent manner.
血管紧张素-II诱导的血管功能障碍可源于对血管和炎症细胞的直接作用以及间接的血流动力学作用。我们使用分离的功能性培养主动脉，旨在确定血管紧张素-II对环氧化酶（COX）和诱导型一氧化氮合酶（iNOS）的影响，并评估它们对血管反应性的影响。将来自小鼠的主动脉环在含有血管紧张素-II（100 nmol/L）或赋形剂的培养基中孵育过夜，以诱导血管功能障碍。在浴槽中评估培养动脉的血管反应性。进行COX-1和COX-2的免疫荧光染色。通过亚硝酸盐水平（一种NO终产物）并使用荧光探针（DAF）来检测一氧化氮（NO）的生成。分别通过DHE荧光和硝基酪氨酸染色来测定氧化应激和亚硝化应激。用血管紧张素-II培养的动脉显示内皮依赖性舒张受损，这被AT受体拮抗剂逆转。抑制COX和iNOS可恢复血管舒张，提示血管紧张素-II触发COX和iNOS，导致血管收缩受体激活的共同途径。此外，使用选择性拮抗剂，确定TP和EP是参与该反应的受体。布洛芬可减弱血管紧张素-II培养的主动脉的内皮依赖性收缩，并且在动脉中发现COX-2免疫染色增加，表明内皮释放血管收缩性前列腺素。血管紧张素-II诱导活性氧和NO生成增加。iNOS抑制剂可防止血管紧张素-II刺激的动脉中NO增强和硝基酪氨酸积累。这些结果证实，血管紧张素-II以iNOS和COX共同依赖的方式引起血管炎症，最终导致内皮功能障碍。
