The effect of high pressure on morphology, expression of alpha-actin and proliferating cell nuclear antigen of vascular smooth muscle cells--a new model of common carotid artery exposed to stress in vivo / 生物医学工程学杂志

ABSTRACT

To investigate the role and mechanism of mechanical stress on arterial remodeling, a new model of common carotid artery exposed to stress in vivo was established in rat, in which the change of pressure is the only influencing factor. The effect of high pressure on the morphology and expression of alpha-actin and proliferating cell nuclear antigen (PCNA) of vascular smooth muscle cells (VSMCs) in the artery was assessed. The arteries were perfused by both high pressure (160 mmHg) and normal pressure (80 mmHg) for 6 hours. The changes of morphology, expression of alpha-actin and PCNA in VSMCs were studied by histology and immunohistochemistry. The results showed that the new model could be controlled well in pressure and frequency. The euchromatin was increased and PCNA-positive particles were observed in the nuclei of VSMCs, but the expression of alpha-actin was decreased when the arteries were exposed to the high pressure. The new model has been successfully established, which provides a new tool for studying the effect of mechanical stress on arterial remodeling. In this experiment, VSMCs underwent a transformation from contractile phenotype into synthetic phenotype and tended to proliferate in response to the high pressure.