Establishment of a novel rat model of different degrees of portal vein stenosis following 70% partial hepatectomy

Abstract

Liver transplantation may fail due to complications of insufficient portal vein (PV) flow such as portal vein stenosis (PVS). Therefore, establishing a model to explore the effect of PV flow on liver regeneration is crucial and essential. Rats were randomly divided into 6 groups: sham operation rats group; 70% partial hepatectomy (PH) group (group A); PVS groups with mild, moderate, or severe stenosis (group B–D) and portal vein ligation (PVL) group. PVS was produced by ligating PV with parallelly placed needles of different gauges. Ultrasound was performed to validate the stenosis ratio (SR) and velocity ratio (VR) at the prestenotic and stenotic site. Rats were sacrificed on day 1,3,7, and 14 after surgery, and liver regeneration rate (LRR) was calculated. We successfully established rat models of different degrees of PVS following 70%PH in 72 rats. The SRs of each PVS group were 44.8 ± 5.23%, 59.3 ± 4.07% and 69.5 ± 2.17%, which showed no statistical differences compared with those measured by stenosis ratio measured by ultrasound. The survival rate in groups A-D were 100%, 83.3%, 66.7% and 50% respectively. Differences were demonstrated between groups A and C, as well as groups A and D (both P<0.05). Moreover, LRR negatively correlated with SR_u and VR, and the correlation coefficients were −0.534 and −0.522, respectively. The rat model we established has the potential to be applied in most conditions of liver regeneration with reduced PV inflow, and it provides a foundation for further exploring the relationship between PV hemodynamic changes and liver regeneration.