Characteristics and feasibility of vessel restenosis models produced by denuding arterial endothelium with domestic-made balloon catheter in rats

Lu WU; Wei ZHANG; Changqing DENG

ABSTRACT

BACKGROUND:

Researches on establishing restenosis models in rats emphasize the importancc of 2.0 Forgarty balloon catheter import,but little has been mentioned about domestic-made balloon catheter.

OBJECTIVE:

To explore the characteristics of vessel restenosis model by denuding arterial endothelium with domestic-made 2.0 Forgarty balloon catheter in rats.

DESIGN:

A randomized controlled animal experiment.

SETTING:

Laboratory of Pathophysiology,Hunan University of Traditional Chinese Medicine.MATERIALsThis study was performed at the Laboratory of Pathophysiology,Hunan University of Traditional Chinese Medicine between September 2006 and January 2007.Healthy male SD rats,weighing 300-350 g,were selected.The protocol was performed in accordance with ethical guidelines for the use and care of animals.Domestic-made 2.0 Forgarty balloon catheters were made of balloons and catheters.Proliferating cell nuclear antigen(PCNA),collagen I,and SM α-actin immunohistochemical staining kits were provided by Wuhan Boster Bioengineering Co.,Ltd,China.

METHODS:

The rats were randomly divided into 4 groupssham-operated group(n=5),7th day model group(n=4),14th day model group(n=5),and 21st day model group(n=4).The vessel restenosis models were established in the latter 3 groups by denuding arterial endothelium with domestic-made balloon catheter in rats.In the sham-operated group,rats were without insertion of balloon catheter.Injured thoracic aortas were taken out for HE staining to observe histological changes of vascular intima.At the meantime,expressions of SM α-actin,PCNA and collagen I were determined by immunohistochemical method in each group.MAIN OUTCOME

MEASURES:

Histological changes of intima at the thoracic aorta as well as expressions of SM α-actin,PCNA and collagen I.

RESULTS:

Eighteen rats were included in the final analysis.The aortal vascular walls remained integrity without narrowness of the lumen areas and proliferation of the endothelium,vascular smooth muscle cells(VSMCs)ranged regularly in the mesolamella in the sham-operated group.The endothelium had little proliferation in the 7th day model group.The intima thickened and the area of lumen became narrow in the 14th day model group.The intimal hyperplasia was diffusive and progressive which mainly included VSMCs,the area of lumen narrowed markedly and cells ranged disorderly in mesolamella in the 21st day model group.In the 14th day model group,PCNA level was higher compared to the remaining 3 groups(P＜0.01).SM α-actin level were significantly higher in the 14th and 21st day model groups than in the sham-operated group and 7th day model group(both P＜0.01).There were no significant differences in collagen I among the groups(P＞0.05).

CONCLUSION:

Vascular intima hyperplasia appeared markedly 14-21 days after domestic-made balloon catheter-induced rat aorta injury.The results suggested that intima hyperplasia is mainly induced by proliferation of VSMCs.