The effects of Xuezhikang on vascular remodeling and aortic fibers in spontaneously hypertensive rats

LIN Zhong-wei; WANG Zhuo; YU Chan; ZHANG Chi-ming; LI Wen-lei; ZHU Yao-yao; CHEN Ying-yu

摘要：Background Xuezhikang is a traditional Chinese medicine for the therapy of patients with cardiovascular diseases.However,the effect of Xuezhikang on vascular remodeling and aortic fibers in spontaneously hypertensive rats remains unclear.Methods Thirty spontaneously hypertensive rats (SHRs) aged 8 weeks were randomized into three groups:SHRs control group (SHRs group,n =10),group treated with low dose Xuezhikang (XZK-L,20 mg/kg/d,n =10) and group treated with high dose Xuezhikang (XZK-H,200 mg/kg/d,n =10).The normal group was comprised of ten Wistar-Kyoto (WKY) rats of the same age.While under pentobarbital anesthesia,in vivo aortic stiffness was determined by a pulse wave velocity (PWV) technique and measured locally in the descending thoracic aorta by Doppler ultrasound echocardiography.Fixed tissues were sectioned and stained with hematoxylin and eosin,masson trichrome,aldehyde-fuchsin and Gordon-Sweets stain.Results The PWV,thicknesses of the aortic wall,wall-to-lumen (W/L) ratio,elastic fibers thicknesses and collagen volume fraction were measured.XZK-L and XZK-H groups were observed to be significantly greater than those in the normal group (P ＜ 0.01).The levels of PWV,W/L ratio and collagen fibers were observed to be significantly reduced in the XZK-H group when compared with the control group (P ＜ 0.05).There was no significance in reticular fiber distributing between the XZK-treated group and SHR group.The reticular fibers in SHR rats were obviously more than those of WKY rats.Conclusion The hypertensive vascular remodeling is associated with changes of elastic fibers and collagen and reticular fibers.Xuezhikang improves hypertensive vascular remodeling by repairing the elastic fibers and inhibiting the levels of collagen.