Morphometric parameters of sinusoidal capillaries, interlobular veins and interlobular arteries at different stages of experimental liver fibrosis

Abstract

The aim of the study was to conduct a morphometric analysis of sinusoidal capillaries, interlobular veins and interlobular arteries of the liver at different stages of experimental fibrosis in order to investigate relationship between fibrogenesis and angiogenesis and identify new therapeutic targets. Material and methods. The study included male Wistar rats. Liver fibrosis with transformation into cirrhosis was induced with a solution of thioacetamide, which was injected into the stomach, dosage 200 mg/kg of animal body weight, using a probe 2 times a week. The rats of the experimental groups were withdrawn from the experiment in 3, 5, 7, 9, 11, 13, 15, and 17 weeks, and the intact ones - at the end of the experiment. To identify connective tissue, liver sections were stained according to the Mallory method. Immunohistochemical examination was performed on paraffin sections using a monoclonal mouse antibody to CD31. The number of sinusoidal capillaries, interlobular arteries, and interlobular veins was counted in three non-overlapping fields of view of each histological section using an OLYMPUS BX51 microscope at a 40× objective magnification. Results. The results obtained supported a statistically significant decreased number of sinusoidal capillaries (p=0,0000) and an increased number of interlobular veins (p=0,0000) in animals of the experimental group compared with the control group. There were no differences in the number of interlobular arteries (p=0,9999). Pronounced angiogenesis in the portal zones and connective tissue septa was associated with an increased amount of the connective tissue during liver fibrogenesis. Conclusion. In the future, angiogenesis modulation should be differentiated and directed towards antifibrotic, anti-inflammatory or autoimmune therapy in chronic liver diseases.