Hepatic VASP upregulation in rats with secondary biliary cirrhosis by expression in the peribiliary vascular plexus

Introduction/aims: Hepatic disorders in patients and animal models may be characterized by increased ductular proliferation and concomitant expansion of the peribiliary vascular plexus (PBP). VASP plays an essential role for the control of cell assembly during the formation of three-dimensional organ structures in the cardiovascular system. Here, we investigated hepatic VASP expression in response to bile duct ligation (BDL) of rats. Methods: BDL was performed in male rats. Sham-operated rats served as controls. After 4 weeks, hepatic VASP expression was assessed by Western-blot analysis and immunohistochemical staining. Results: Livers of BDL rats showed excessive formation of new bile ducts. VASP mRNA and protein expression was upregulated in whole liver homogenates from BDL rats. This upregulation was located to the expanding PBP in the areas of ductular proliferation. In patients with cirrhosis, hepatic VASP expression was upregulated compared to non-cirrhotic patients. Discussion: VASP may play a role for vascular morphogenesis in the expanding PBP of BDL rats.