The Antihypertension Effect Of YXQN On Spontaneous Hypertension Rat (SHR) And The Protective Effect On SHR Heart

Objective: To investigate the antihypertension effect of YXQN on Spontaneous Hypertension Rat (SHR) and search for YXQN's protective effect on SHR heart. Method: By using SHR, blood pressure measuring machine and several biochemical techniques, we performed our works in the following five items: (1) Measure blood pressure in 4 and 24 hours after the rat was treated with YXQN one time (2) Survey the changes of left ventricular hypertrophy (LVH) caused by hypertension by using left ventricular weight (LVW) and LVW to body weight (BW) ratio (3) Survey the changes of left ventricular myocardial collagen by measuring contain of hydroxyproline (4) Observe type I to type III collagen ratio by using SDS electrophoresis (5) Observe the changes of related genes by DNA microarray. Result:(1) Treating with YXQN one time can reduce the blood pressure of SHR. One hour after YXQN was treated we observed the effect of reducing blood pressure and the peak is after 2 to 4 hours. The blood pressure reduced significantly after 2 hours and the peak is after 3 hours about 9mmHg. The blood pressure is 2mmHg lower than origin after 24hours. The middle and low dose groups also reduce the blood pressure but not yet to the extent of that of high dose group.(2) Different dose groups of YXQN can reduce the blood pressure of SHR. Two weeks after YXQN was treated continuously, the blood pressure is reduced significantly in high dose group compared with model group. YXQN can prevent the development of blood pressure while rats grows.(3) Different dose groups of YXQN can reduce LVW and the effect is significant between high dose group and model group. They also can reduce the ratio of LVW to BW and the effect of middle and high dose groups is significant compared with model group. The effect of high dose group is better than Captopril Tablets group.(4) Different groups can reduce contain of left ventricular myocardial collagenand type I to type III collagen ratio. The effect of middle dose group is significant in reducing contain of collagen. The effect of all groups is significant in reducing ratio of type I to type III collagen.(5) The genes latent transforming growth factor binding protein 2 (LTBP-2), glycine methyltransferase (Gnmt) and rat beta-galactoside-alpha 2.6-sialyltransferase in YXQN group were expressed in lower level than in model group. The genes CD36 antigen, heart fatty acid binding protein (Fabp3) and propionyl Coenzyme A carboxylase beta polypeptide (Pccb) in YXQN group were expressed in higher level than in model group. They may play an important role in preventing LVH Conclusion:(1) Treating with YXQN one time can reduce the blood pressure of SHR.(2) YXQN can prevent the development of blood pressure while rats grows.(3) YXQN can prevent and reduce the development of LVH.(4) YXQN can reduce contain of myocardial collagen and type I to type III collagen ratio, therefore prevent and reduce left ventricular remolding.(5) YXQN can lower the express level of LTBP-2 .