[Effect of paeonol on blood pressure and blood flow in artery of spontaneously hypertensive rats and its mechanisms related on vasomotion].

Previous studies have shown that paeonol can antagonize acute myocardial ischemia and infarction in rat. This study further researched the effects of paeonol on blood pressure and blood flow in the artery of spontaneously hypertensive rats and its mechanisms related on vasomotion. Firstly, thirty spontaneously hypertensive rats were randomly divided into spontaneously hypertensive control group and paeonol-treating groups of high dose and low dose, and also, the other ten Wistar rats as healthy control group. Before and after the intraduodenal administration of the drug, arterial blood pressure was measured by carotid artery and blood flow through the renal artery and carotid artery in vivo were measured by animal flowmeter. The same volume of solvent was given to the spontaneously hypertensive control group and the healthy control group, and the other operations were same. In order to further study the effect of paeonol on vasomotor function, the superior mesenteric artery, renal artery and coronary artery of the spontaneously hypertensive rat were removed and separated, precontracted by a certain concentration of potassium chloride (KCl) and 5-serotonin (5-HT) respectively, and dilatory responses were assessed by cumulative addition of paeonol. Results showed that after duodenal one-time delivery of paeonol, the blood pressure significantly lowered, the renal arterial blood flow and the carotid arterial blood flow significantly increased in spontaneously hypertensive rat. And also, paeonol relaxed the mesenteric artery, renal artery and the coronary artery of spontaneously hypertensive rat in a concentration-dependent manner. These results indicated that the effect of paeonol on decreasing arterial blood pressure and increasing the arterial blood flow was related to its vasodilative effect.