Abstract:

This study was performed to investigate the effect of blueberry juice and blueberry anthocyanins with various purities
on blood pressure of spontaneously hypertensive (SHR) rats aged 12 weeks. The rats were separated into four groups: group A
was administered by gavage with blueberry juice (containing 1.00% anthocyanins), and groups B, C and D were administered
orally with 8.66%, 38.49% and 94.42% anthocyanins, respectively. The doses, calculated based on anthocyanins content, were
94.4, 472.1 and 944.2 mg/kg body weight (bw) for group A, 10.9, 54.5 and 109.0 mg/kg bw for group B, 2.5, 12.3 and 24.5 mg/kg bw
for group C, and 1.0, 5.0 and 10.0 mg/kg bw for group D. The results showed blueberry juice and blueberry skin extracts
containing different amounts of anthocyanins, when used at the same doses (anthocyanins equivalent), presented a significant
difference (P ＜ 0.05) in their antihypertensive effect on SHR rats. However, no significant difference in antihypertensive
activity was observed between blueberry anthocyanins with different purities when used at same doses (P ＞ 0.05). At 4 or 5
h after high-dose administration of blueberry juice and blueberry anthocyanins with three different purities, the systolic blood
pressure of SHR rats was reduced by 38.45, 32.57, 33.09, and 33.41 mmHg, respectively. Therefore, blueberry anthocyanins
can ameliorate in SHR rats, and this effect is enhanced by other active components of blueberry juice.

Key words: blueberry juice, anthocyanins, hypertension, spontaneously hypertensive rats (SHR)