Soy isoflavones enhance coronary vascular reactivity in atherosclerotic female macaques.Author: Honoré EK. Publication: Fertility and Sterility. 1997, 67, 148-154.
The objective of this study was to investigate the effects of soy isoflavones on coronary vascular reactivity in atherosclerotic rhesus monkeys. The study was carried out on 22 young adult rhesus monkeys which had atherosclerosis induced by a previous diet.
Monkeys were divided in 2 groups and were fed during six months with soy based diet:
Group 1: the soyfood contained their natural isoflavones
Group 2: the isoflavones were removed from the diet
After the 6 months quantitative coronary angiography was performed. The female monkeys underwent a second angiography after an acute dose of genistein. The diameter of the proximal left circumflex coronary artery was measured after injection of acetylcholine and nitroglycerin. The arteries of males monkeys constricted in response to acetylcholine. The arteries of females monkeys in group 2 constricted, whereas arteries from females in group 2 dilated. This study demonstrated that dietary soy isoflavones enhance the dilator response to acetylcholine of atherosclerotic arteries in female monkeys.Dietary isoflavones: biological effects and relevance to human health. J Nutr. 1999 Mar;129(3):758S-767S