Cardiovascular effect of Artemisia herba alba aqueous extract in spontaneously hypertensive rats

This study aimed to evaluate the hypotensive activity of Artemisia herba alba aqueous extract (AHAE) in spontaneously hypertensive rats (SHR). AHAE was lyophilized and administered daily at a dose of 150 mg/kg for 20 days. AHAE administration produced a significant reduction in systolic blood pressure after 8 days of oral administration (P < 0.01), and a sustained reduction was observed at the end of treatment (P < 0.01). Heart rate remained unchanged during the 20 days of oral AHAE administration. In addition, AHAE administration produced a significant increase in urinary output (P < 0.01) and glomerular filtration rate (P < 0.01) on day 8 of treatment. Urinary electrolyte excretion was also modified during the 20 days of AHAE administration, and a significant increase in urinary sodium and potassium excretion was observed from day 4 (P < 0.01) to day 20 (P < 0.001). However, urinary chloride excretion was increased from day 8 (P < 0.01) to the end of treatment (P < 0.001). The hypotensive effect appeared to be independent of the renin-angiotensin system since AHAE did not affect plasma angiotensin-converting enzyme or renin activities (P > 0.05) after 20 days of oral administration. We conclude that AHAE possesses antihypertensive activity in SHR and that the underlying mechanism appears to involve, at least in part, an increase in urine and electrolyte output.