Nutr Res Pract.  2012 Aug;6(4):308-314.

The antihypertensive effect of ethyl acetate extract of radish leaves in spontaneously hypertensive rats

• Chung DH
• Kim SH
• Myung N
• Cho KJ
• Chang MJ

Abstract

Radish (Raphanus sativus L.) is a cruciferous vegetable, and its leaves have antioxidant and anticancer properties. This study was conducted to evaluate the effects of ethyl acetate extracts from radish leaves on hypertension in 11-week-old spontaneously hypertensive rats (SHRs). The SHRs were randomly divided into 3 groups of 6 rats each on the basis of initial systolic blood pressure (SBP) and were treated with oral administration of radish leaf extract (0, 30, or 90 mg/kg body weight [bw], respectively) for 5 weeks. Six Wistar rats were used as normotensive controls. The amount of the radish leaf extract had no effect on body weight. The SBP of the SHRs showed a decreasing trend with the consumption of the radish leaf extract. In the third week, the SBP of the group fed 90 mg extract/kg bw reduced from 214 mmHg to 166 mmHg and was significantly lower than that of the normotensive and hypertensive controls. The extract did not show a significant effect on the angiotensin-converting enzyme (ACE) activity in the serum, kidney, and lung. The extract increased the concentration of NO in serum and the activities of antioxidant enzymes such as glutathione peroxidase and catalase in red blood cells (RBCs). The serum concentrations of Na+ and K+ were not significantly different between all groups. However, the fecal concentrations of Na+ and K+ increased; the fecal concentrations of Na+ and K+ for the normotensive and hypertensive controls were not different. Urinary excretion of Na+ was higher in the normotensive Wistar rats than in the SHRs, while that of K+ was not significantly different. These findings indicate that consumption of radish leaves might have had antihypertensive effects in SHRs by increasing the serum concentration of NO and fecal concentration of Na+ and enhancing antioxidant activities.

Keyword

Radish (Raphanus sativus L.) leaf ethyl acetate extract; spontaneous hypertension; ACE; antioxidant enzyme activity

MeSH Terms

Acetates
Administration, Oral
Animals
Blood Pressure
Body Weight
Catalase
Erythrocytes
Glutathione Peroxidase
Hypertension
Kidney
Lung
Raphanus
Rats
Rats, Inbred SHR
Rats, Wistar
Vegetables
Acetates
Catalase
Glutathione Peroxidase

Figure

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  Fig. 1 Systolic blood pressure over 5 weeks. Points are expressed as the means ± SEM, n = 6 rats per group. Values with different superscripts in a single week are significantly different (P < 0.05) as assessed by one-way ANOVA and the Duncan's multiple range test. WC, Wistar normotensive control; SC, spontaneously hypertensive control; SL, hypertensive rats with low extract intake; SH, hypertensive rats with high extract intake.

• 

  Fig. 2 ACE activity in the lung, kidney, and serum. Bars represent means ± SEM, n = 6 rats per group. WC, Wistar normotensive control; SC, spontaneously hypertensive control; SL, hypertensive rats with low extract intake; SH, hypertensive rats with high extract intake.

• 

  Fig. 3 Serum nitric oxide concentration. Bars represent means ± SEM, n = 6 rats per group. Values with different superscripts are significantly different (P < 0.05) as assessed by one-way ANOVA and the Duncan's multiple range test. WC, Wistar normotensive control; SC, spontaneously hypertensive control; SL, hypertensive rats with low extract intake; SH, hypertensive rats with high extract intake.

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