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.