Planta Medica ( IF 2.7 ) Pub Date : 2024-01-25 , DOI: 10.1055/a-2240-7372 Kaori Katiuska Yamaguchi Isla 1 , Mirtes Midori Tanae 1 , Maria Teresa Riggio de Lima-Landman 1 , Pedro Melillo de Magalhães 2 , Antônio José Lapa 1 , Caden Souccar 1
Cuphea carthagenensis (Jacq.) J. F. Macbr. is a popular plant in Brazilian folk medicine owing to its hypotensive and central nervous system depressant effects. This study aimed to validate the hypotensive effect of the plantʼs aqueous extract (AE) in rats and examine the vascular actions of three hydrolyzable tannins, oenothein B, woodfordin C, and eucalbanin B, isolated from AE. Systolic blood pressure in unanesthetized rats was determined using the non-invasive tail-cuff method. Oral treatment of normotensive rats with 0.5 and 1.0 g/kg/day AE induced a dose-related hypotensive effect after 1 week. In rat aortic rings pre-contracted with noradrenaline, all ellagitannins (20 – 180 µM) induced a concentration-related vasorelaxation. This effect was blocked by either removing the endothelium or pre-incubating with NG-nitro-