Low grade cirrhosis induces cognitive impairment and motor dysfunction in rats: could be a model for minimal hepatic encephalopathy.

Hepatic encephalopathy (HE) is a nervous system disorder developed in the patients with liver cirrhosis. The low grade cirrhosis is of common occurrence, however, whether and the extent to which it affects brain function is not clearly understood. The present article examines certain neurobehavioral parameters in the rats with low grade chronic liver failure (CLF) induced by intraperitoneal administration of 50mg/kgb.w. thioacetamide up to 14 days. During Morris Water Maze tasks, the CLF rats, as compared to the control, showed insignificant decline in the escape latency score to find out the hidden platform throughout the learning days and also stayed for a significantly declined (p<0.01) time period at the place of the hidden platform during the retrieval test. They also showed impairment in the conditional discrimination ability, reflected by a significant decline in the active avoidance score (p<0.05) and increment in the number of non-response (p<0.05) during shuttle box tests. On rotarod performance, they exhibited significant decline in their riding time (p<0.01-001) on the rotating rod as a function of increasing speed. The findings suggest a moderate level cognitive impairment and motor dysfunction in the low grade CLF rats. Since, these impairments correlate with the early stage manifestation of HE in the patients, these CLF rats could serve as a model to study the pathogenesis of minimal hepatic encephalopathy.