IN VITRO CARACTERIZATION OF AVELOZ LATEX EFFECTS ON AORTA VASCULAR REACTIVITY

IN VITRO CARACTERIZATION OF AVELOZ LATEX EFFECTS ON AORTA VASCULAR REACTIVITY

• Autor
• Thamirys Maria Pandolfi da Fraga da Silva
• Co-autores
• Edgar Hell Kampke , Maria Eduarda Souza Barroso , Bianca Prandi Campagnaro , Agata Lages Gava , Elisardo Corral Vasquez , Ricardo Machado Kuster , Silvana dos Santos Meyrelles
• Resumo

• Studies have appointed low Euphorbia tirucalli (Aveloz) cytotoxicity, however, there aren´t any research showing its effects in a whole organ. Our goal was to investigate Aveloz effects in the aorta. Twenty-one male Wistar rats, 3 months old, were euthanized and thoracic aorta dissected, cutted and rings placed in an organ bath. We evaluated vascular responses to phenylephrine (Phe 10^-10 to 3x10^-5 M), acetylcholine (Ach 10^-10 to 10^-5 M) and sodium nitroprusside (NPS 10^-10 to 10^-5 M) before (control, Ct) and after Aveloz incubation (AV 50ng/mL). Some aortic rings were also incubated with L-NAME (100 ?M). Differences in maximum response (Rmax), sensitivity (pD2) and area under the curve (dAUC) were evaluated. Results were expressed as mean ± SEM. ANOVA and Test t were used, and differences were considered significant when p<0.05. This study was approved by CEUA-UFES number 09/2019. Vasoconstriction with Phe showed a reduction in Rmax after AV incubation at dose 10^-5 compared to CT aortic rings (72±20% vs. 85±62% respectively, p>0.05). Endothelium-dependent vasodilator response to Ach decreased after aortic ring incubation with AV when compared to CT rings (Rmax: 54±3% vs. 82±5%; dAUC: 225±03 a.u. vs. 288±7 a.u. respectively, p<0.05). Endothelium independent relaxation showed a difference in sensitivity after incubation with AV compared to CT (Emax: 101±07% vs. 100±24%; pD2: 5±0.5 vs. 7±0.2; dAUC: 275±58 a.u. vs. 394±63 a.u., respectively, p>0.05). When L-NAME was applied, vasodilator response to Ach was totally abolished in AV group. Removal of aorta endothelial cells decreased Phe vasoconstrictor response in AV incubated aortic rings vs. control (Rmax: 55±6% vs. 82±4 %; dAUC: 203±7 a.u. vs. 261±5 a.u., respectively, p<0.05). Our results shown that AV can acutely interfere with vessel function by decreasing the endothelium vasodilator response to Ach. This decrease was greatly exacerbated when eNOS inhibitor L-NAME was incubated with AV. 

• Palavras-chave
• Aveloz, L-NAME, Vascular Reactivity
• Modalidade
• Comunicação oral
• Área Temática
• Produtos naturais