Inferior vena cava stenosis-induced deep vein thrombosis is influenced by multiple factors in rats.

BACKGROUND:The pathogenesis of deep vein thrombosis (DVT) is incompletely understood, requiring reliable animal models. Inferior vena cava (IVC) stenosis model mimics human DVT. OBJECTIVE:To provide optimal conditions for establishing a rat model of IVC stenosis-induced DVT. METHODS:Effects of suture, and body weight, sex and side branches of rats on the IVC stenosis model were evaluated. 1 d after modeling, the weight and length of thrombosed IVCs and side branch distance were measured. Histopathological change and leukocytes influxes were observed by hematoxylin and eosin staining. Ly-6G-positive neutrophils were located by immunofluorescence. A multiple regression linear model was then built. RESULTS:IVCs stenosed with silk or monofilament sutures presented no difference in leukocyte influxes. Thrombus of 220-340 g rats was significantly heavier than that of 180-220 g rats. Although no statistic difference was found in thrombus weight between male and female rats weighing 180-260 g, males weighing 260-300 g formed larger thrombi than weight-matched females. Thrombus weight and length of rats except 180-220 g females was not impacted by side branch ligation and side branch distance. The regression model showed that sex and body weight were key factors affecting thrombus weight. CONCLUSIONS:Male and female rats weighing 220-260 g are more suitable for establishing a model of DVT induced by stenosing IVC with silk and without side branch ligation.