IJCS | Volume 32, Nº2, May/June 2019

DOI: 10.5935/2359-4802.20190009 207 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2019;32(3)207-216 Mailing Address: Natacha Pinheiro Melo Brozzo Rua Hechem Fahat, 151. Postal Code: 69918-584, Vila Ivonete, Rio Branco, AC - Brazil. E-mail: natachabrozzo@gmail.com, natacha_ieq@hotmail.com Curcuma Longa Abolishes Phenylephrine-Induced Contractions in Isolated Aortic Artery of Rats Natacha Pinheiro Melo Brozzo, 1 E fraim dos Santos Ferreira, 1 E duardo Andrade Gonçalves, 1 D ionatas Ulises de Oliveira Meneguetti, 1, 3 D elano Aníbal da Silva, 1, 2 R enildo Moura da Cunha 1 Universidade Federal do Acre, Rio Branco, 1 AC - Brazil Faculdade Meta (FAMETA), 2 Rio Branco, AC - Brazil Colégio de Aplicação da UFAC, 3 Rio Branco, AC - Brazil Manuscript received February 24, 2017; revised manuscript September 04, 2018; accepted September 24, 2018. Abstract Background: Curcuma longa has biological effects. Its cardiovascular activities are yet to be scientifically studied. Objectives: To investigate the vasorelaxant effects of the aqueous extract of Curcuma longa (AECL). Methods: Aortic annuli of normotensive rats, with or without endothelium, were set up in a data storage systemwith nutrient solution in recipients, with scientifically recommended temperature, aeration and tension. Over contraction by Phenylephrine, the AECL (1, 3, 10, 30, 100, 300 and 1000 μg/mL) was incubated before and after incubation with atropine or L-name or indomethacin. An AECL concentration-response curve was also built over contractions caused by elevation of extracellular K + . Data were significant when p < 0.05, with GraphPad Prism 6.0 software resolutions. Results: The AECL induced 100%vasorelaxation also in the endothelium-free annuli. The part of the endothelium- dependent effect had EC 50 = 4.32 ± 0.05 μg/mL. With inhibition of NO production, the EC 50 increased to 126.50 ± 2.35 μg/mL; after inhibition of prostacyclin production, to 124.6 ± 0.05 μg/mL; and after muscarinic blockade, to 437.10 ± 0.2 μg/mL. Opening of K + channels (relaxation of 56.98%) and VOCC blockade (relaxation of 31.56%) were evident. Conclusion: AECL induced significant vasorelaxation, being more significant in the presence of endothelium. The muscarinic pathway seems to be the main one involved in this effect, followed by the NO production and prostacyclin pathways. The activity in K + channels by AECL was more significant than its VOCC blockade. The use of other models and tools to study action mechanisms will be important and elucidating. (Int J Cardiovasc Sci. 2019;32(3)207-216) Keywords: Curcuma/adverse effects; Crocus; Receptors, Muscarinic; Vasodilator Agents; Cardiotonic Agents; Antioxidants; Hypertension. Introduction According to the World Health Organization (WHO) and the Pan American Health Organization (PAHO), heart diseases are one of the major causes of death worldwide1 and in low- and middle-income countries, more than three-quarters of the deaths are due to cardiovascular diseases. 1,2 Hypertension is themainriskfactor for thedevelopment of cardiovascular diseases, affectingmore than one billion people worldwide. 3-5 The use of allopathic drugs has been the main type of therapy used to fight hypertension and, consequently, all the other diseases that result from it, even though it is known that one of the major problems of this treatment option are its side effects. 5 Recently, more attention has been paid to the use of medicinal plants to attenuate the damage of several diseases, including arterial hypertension. 6,7 The rhizome of Curcuma longa Linnaeus , which belongs to the Zingiberaceae family of Malay-Indigenous origin, 8 popularly known as Yellow Ginger or Saffron, was used only as a food dye in many countries, and its