Avaliação da reatividade vascular de extratos e substâncias aquosas obtidos de preparações de bebida mate (Ilex paraguariensis St. Hil) em aorta de ratos

Abstract

Introduction: Ilex paraguariensis is a plant belonging to the Aquifoliaceae family, commonly used by the population of Argentina, Brazil, and Paraguay, and popularly known as mate. It is consumed in various preparations, notably both cold and hot. Studies have shown that the plant contains various organic compounds with diverse biological effects, such as anti-inflammatory and antioxidant properties, and has proven effective in improving endothelial function and protecting vascular function in consumers, also preventing the development of atherosclerosis. In this context, systemic arterial hypertension (SAH) is significant, as it is one of the main factors of morbidity and mortality worldwide. The main objective of this study was to evaluate the vasorelaxant capacity of Ilex paraguariensis preparations and compounds, as well as the mechanism of action involved, through vascular reactivity studies in isolated aorta of Wistar rats. Materials and Methods: The animals were euthanized, followed by thoracotomy to expose their aorta. The aorta was removed, cleaned, and divided into aortic rings with and without endothelium. The rings were placed in baths with modified Krebs-Henseleit solution and connected to transducers. The extracts were obtained through aqueous preparations simulating the consumption of mate by the population. Results: The preparations demonstrated vasorelaxant activity, with a rate of 54.93% ± 0.17 in aorta with endothelium and 52.35% ± 0.02 in aorta without endothelium. Caffeine, the major compound, exhibited a vasorelaxant effect of 100%. The suggested mechanism of action involves the activation of potassium (K+) channels activated by calcium (Ca2+). Conclusion: Preparations and isolated compounds of Ilex paraguariensis showed significant antihypertensive activity in isolated organ study models, demonstrating promise as an ally in the treatment of systemic arterial hypertension. The possible mechanism of action involves the activation of potassium (K+) channels activated by calcium (Ca2+), likely attributed to caffeine, the major compound of the plant.