Changes in Arterial Blood Pressure of a Soluble Cocoa Fiber Product in Spontaneously Hypertensive Rats

Abstract

The effect produced by long-term intake of a soluble cocoa fiber product (SCFP) on the development of hypertension of spontaneously hypertensive rats (SHR) was evaluated. Twenty male 3-week-old SHR were divided into two groups of 10 animals that drank either tap water (control) or a solution of SCFP (0.75 g/day SCFP) until the 20th week of life. Five 20-week-old rats of each group were sacrificed. Tap water as drinking fluid was given to all the animals from the 20th to 24th week of life. The 24-week-old rats were also sacrificed. Body weight, liquid and dry food intake, and arterial blood pressure (tail cuff) were recorded weekly. Malondialdehyde (MDA), glucose and angiotensin converting enzyme (ACE) activity in the plasma from the sacrificed rats were also obtained, and we evaluated the relaxation caused by acetylcholine in the aorta from these animals. SCFP attenuated the development of hypertension in SHR; however, the withdrawal of SCFP caused an increase in blood pressure in the rats. Body weight gain was slower in the group treated with SCFP. SCFP increased liquid intake but decreased dry food intake in the rats. SCFP decreased plasma MDA concentrations and slightly decreased plasma ACE activity, but no differences were observed in plasma glucose and in the aorta responses to acetylcholine in both groups of 20-week-old SHR. We have demonstrated the antihypertensive and antioxidant properties of SCFP. The control of body weight and the control of increased angiotensin II may be involved in the antihypertensive effect of this product.