Abstract: To observe the antagonizing hypertensive effect of Qindan capsule on spontaneous hypertensive rats (SHRs) and detect its possible mechanism. Methods: Forty SHRs were divided into 5 groups: high and low dose of Qindan capsule groups, Niuhuang Jiangya capsule group, Captopril group and model group, and 8 WistarKyoto (WKY) rats were acted as normal control. Each group was given relevant medicine. Blood pressure (BP) of each group and the level of endothelin (ET), calcitonin generelated peptide (CGRP), AngII in plasma and AngII in tissues of mesenteric artery were detected 14 weeks later. Results: BP was lower in high dose Qindan capsule group than in model group (P＜0.01), which was not significantly different compared with Captopril group (P＞0.05) and Niuhuang Jiangya capsule group (P＞0.05). Compared with model group, Qindan capsule was superior to Niuhuang Jiangya capsule and Captopril in reducing the concentration of ET in plasma and in raising the plasmic CGRP (P＜0.05, respectively); Though it had no marked effect on reducing AngII in plasma compared with other groups (P＞0.05), it could decrease the concentration of AngII in tissues of mesenteric artery (P＜0.01). Conclusion: Qindan capsule has satisfied effect of antagonizing hypertension. The mechanism may be associated with the regulation of vasoactive peptide in plasma and regional renninangiotensin system.

Key words: Qindan capsule, Hypertension, Rats, inbred SHR