title: Acute portal hypertension models in dogs: low- and high-flow approaches.
abstract: Effective animal models are needed to evaluate the feasibility of new techniques to assess portal hypertension (PH). Here we developed 2 canine models of acute PH by increasing intrasinusoidal resistance and by increasing the portal vein (PV) flow volume to test the efficacy of a noninvasive  technique to evaluate PH. The acute low-flow PH model was based on embolization of liver circulation by using a gelatin sponge material. The acute high-flow PH model was based on increasing the PV flow volume by using an arteriovenous (A-V) shunt from the femoral artery and saline infusion.  PV pressures and diameters were assessed before and after inducing PH. Pressure values and diameters were obtained from the inferior vena cava in 3 unmanipulated controls. The low-flow model of PH was repeatable and successfully increased PV pressure by an average of 16.5 mm Hg within 15 min.  The high-flow model of PH failed to achieve increased PV pressures. However, saline supplementation of the portal circulation in the high-flow model led to mean increases in PV pressures of 12.8 mm Hg within 20 min. Pulsatility in the PV was decreased in the low-flow model and increased in  the high-flow model relative to baseline. No changes in PV diameter were noted in either model. These acute PH models are relatively straightforward to implement and may facilitate the evaluation of new techniques to assess PH.
authors.affiliation: Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Jaydev K
authors.initials: JK
authors.lastname: Dave
authors.forename: Ji-Bin
authors.initials: JB
authors.lastname: Liu
authors.forename: Valgerdur G
authors.initials: VG
authors.lastname: Halldorsdottir
authors.forename: John R
authors.initials: JR
authors.lastname: Eisenbrey
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Merton
authors.forename: Priscilla
authors.initials: P
authors.lastname: Machado
authors.forename: Hongjia
authors.initials: H
authors.lastname: Zhao
authors.forename: Joseph
authors.initials: J
authors.lastname: Altemus
authors.forename: Laurence
authors.initials: L
authors.lastname: Needleman
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Brown
authors.forename: Flemming
authors.initials: F
authors.lastname: Forsberg
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D006975:Hypertension, Portal / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008099:Liver / Q000098:blood supply*; D012039:Regional Blood Flow / Q000502:physiology*; D014463:Ultrasonography; D014690:Venous Pressure / Q000502:physiology