Characteristics of vascular remodeling in pregnant hypertensive rats induced by L-NAME / 医用生物力学

ABSTRACT

Objective To elucidate the characteristics of vascular remodeling in pregnant hypertensive rats.Methods Pregnant rats were induced by L-nitro-arginine methylester (L-NAME) to build hypertension models and normal pregnant rats were used as control.Using a programmable sphygmomanometer,the blood pressure was recorded with the tail-cuff method to ensure the hypertension model was successfully replicated.The changes of mean shear stress were determined after the blood viscosity,the average blood flow and the inner diameter in left common carotid artery were measured.To analyze the degree of arterial remodeling,the protein expression levels of collagen Ⅰ (Col Ⅰ) and Ⅲ (Col Ⅲ) were detected by Western blotting,and the media thickness,the inner diameter,the opening angel both in thoracic aorta and carotid artery were determined.Results The mean shear stress of common carotid artery was reduced by (28.52 ± 3.08) ％ with the blood viscosity increasing and the average blood flow decreasing in pregnant hypertensive rats.Compared with control groups,the ratio of media thickness and inner diameter significantly increased in thoracic aorta and carotid artery,while the opening angel decreased in carotid artery and increased in thoracic aorta.With the expression of Col Ⅰ decreasing and Col Ⅲ increasing,the ratio of Col Ⅰ and Col Ⅲ went an apparent decline.Conclusions The mean shear stress is descending in pregnant hypertensive rat,with the remodeling of thoracic aorta and carotid artery.These results may provide new experimental references for further illustrating pathogenesis of pregnant hypertension.