Time course of histopathological changes after bleomycin sclerotherapy in rabbit gallbladders as a model for simple hepatic cysts

Abstract

Bleomycin sclerotherapy is used in the treatment of cystic lesions; however, the histopathological changes are undefined. Present animal models of cystic diseases are not adequate for the study of sclerotherapy of hepatic cysts, primarily because the established cysts in these models are too small in size. The aim of the present study was to establish a new animal model of simple hepatic cysts, and assess the histopathological changes after bleomycin sclerotherapy. Rabbit gallbladder, with ligaturing of the cholecystic duct whilst preserving cholecystic vessels, was used as a model for simple hepatic cysts. Bleomycin (2 mg dissolved in 1 ml saline) was injected into the aspirated gallbladder, gallbladder tissue was harvested (after 1, 7, 14, 28, 42, 56 and 84 days) and histopathological changes were evaluated (n=4 per group). Additionally, control rabbit gallbladders were injected with 1 ml saline and sampled after 14 days (n=4). Histopathological changes were evaluated using hematoxylin-eosin and Masson's trichrome staining, and immunohistochemistry for CD20-, CD43-and CD68-positive cells was performed. The integrated optical density (IOD) of immunohistochemical staining and average positive stained area percentage (APSAP) of collagen were quantitatively analyzed. The results revealed gallbladders in the control group had regular epithelial cells with no visible inflammation or fibrosis. In the experimental group, epithelial cells were swollen and necrotic on the first day, and were replaced gradually by single-layer flat cells from day 56. Inflammatory infiltration was found in the submucosa, and the IOD of T cells, B cells and macrophages were highest on day 1, and these parameters declined gradually, eventually disappearing. The APSAP of collagen was highest on day 7, and gradually declined thereafter. The results suggest that histopathological changes after bleomycin sclerotherapy of a simple hepatic cyst model were characterized by sequential epithelial destruction, inflammatory cell infiltration, collagen proliferation and epithelial partial regeneration.

Targeting of gallbladder megalin receptors with DHA-conjugated limonene albumin nanoparticles

“…6 The deposited lipid droplets can be hydrolyzed into free cholesterol by cholesterol ester hydrolase because its main component is cholesterol ester, 7 and it then returns to the liver to be metabolized into bile salts through the microcirculation of the submucosa. 8,9 Because the structure of the lymphatic and blood vessels of the submucosa of the gallbladder have not been destroyed, 10 and there are cases where cholesterol flows back into the liver, drug intervention can be used for treatment. 11 Studies of some modern medicines include their effect on bile secretion, but only a few of them can promote bile secretion, have the effect of dissolving stones, and improve bile composition.…”