Comparative Evaluation of Neuropathological Lesions Progression in Different Brain Areas in A Rat Model of Chronic Hepatic Encephalopathy

Abstract

Hepatic encephalopathy (HE) is considered a serious clinical complication of acute and chronic liver injury. Previous researches elucidated HE but the characterization of neuropathology in different brain areas is limited. The present study is conducted to evaluate the progression of neuropathological lesions in different brain areas in a rat model with liver fibrosis induced by thioacetamide (TAA). For this experiment, 20 male rats were divided into two groups control and TAA-treated group that was I.P injected twice a week with 100 mg/kg.b.w TAA dissolved in saline for 3 months. Three rats from each group were euthanized after 3 months and the liver specimens were collected for ensuring the development of a rat model for liver fibrosis. The remained rats were kept without further treatment with TAA for 2 months, rats were carefully monitored for abnormal signs. After the end of the experimental period, rats were euthanized and the brains were collected for histopathological examination. Microscopic examination of the brain revealed various neuropathological lesions that varied in severity between different brain areas. The most severe lesions were recorded in the midbrain and pons while mild lesions were detected in the cerebral cortex and striatum. The brain lesions comprised varied degrees of neuronal degeneration with marked astroglial and microglial reactions in the different brain regions. The obvious inflammatory reaction indicates that neuroinflammation plays an important role in the mediation of HE.