Hippocampal early changes in a minimal hepatic encephalopathy rat model

PERAZZO JC; TALLIS S; CALTANA L; ARONNE MP; DELFANTE A; SOUTO P; REINES A, BRUSCO HA

Val-David, Canadá

Simposio; 14th ISHEN Symposium; 2010

International Society on Hepatic Encephalopathy and Nitrogen Metabolism

Graded portal-vein stenosis was used to induce rat minimal hepatic encephalopathy (MHE) whose main features are portal hipertensión, moderate hyperammonemia and hippocampal mitocondrial alterations. These features were well established by day 14 post stenosis. We present a new view that shows the features on the 10th day after stenosis in the rat hippocampus. Glial fibrillar acídica proteína (GFAP) specific for astrocytes (A), S100b proteína localizad in the cytoplasm of A, Nestine (N) localizad in A, perycites and endotelial cells (ECs), microtubule associated proteína 2 (MAP-2) and neurofilament 200kDa, dendritic markers, Lycopersicum esculentum (tomato lectin) for microglia, and Neuronal specific marker, were evaluated by immunohistochemistry. Beside this, Triphenyltetrazolium (TTC) as a dye for hypoxic areas in rat´s brain and Hypoxia inducible factor 1a (HIF-1a) was evaluated by western blot technique and by immunohistochemistry. At day 10 A, GFAP+ cells, were increased in number and with morphological changes as well as Ecs, N+. TTC was highly positive in hippocampus and HIF-1ª  showed a significant increase in hippocampus at day 10, no significant differences were found in frontal cortex (day 10) and in both hippocampues and frontal cortex  at day 14. While Avoidance was altered at day 14 but no significant at day 10, analgesic effect was not observed at any time point. Taking whole data, alterations in the respiratory chain previously reported, astrogliosis and angiogenesis both with morphological changes and the surprisingly hippocampal hypoxia we can concluye that by now these are the earliest changes documented in this model fo MHE.