Cerebellar and Neuro-Behavioural Evaluation of Adult Wistar Rats in Long-Term Exposure to Refuse Dump Site

The present study examined the possible effects of long term exposure of wistar rats to refuse dump site. Young adult wistar rats of approximately 70 days old were housed in the vicinity of a refuse dump site for 5 months, and studied in the Morris water maze (MWM) for learning and memory, in open field for exploratory and locomotor activity and in elevated plus maze for measures of anxiety. The rats were again taken back to the site and kept for a total of 8 months and again studied in the same apparatus. The histology of the experimental animals showed increase vacuolations in the medulla. Also few classic appearance of eosinophilic (degenerating) purkinje neurons with condensed nucleus and bright eosinophilic cytoplasm were seen. There was significant decrease in the % Time in open arms entry after 5 and 8 months (7.45±3.43, 5.744±1.31) of exposures, when compared to control (35.18±13.55). There was no significant difference in % Open arms entry and number of exploratory head dips on the elevated plus maze. In the open field activity, there was significant difference in line crossings only after 8 months (0.71±0.47) of exposure when compared to control (2.83±0.54) and also to 5 months group (3.25±0.30). There was no significant difference in Latency both at 5 months and 8 months of exposure compared to control. Also there was no significant difference in probe trial value of the exposed rats.

Key Words: Open arms, Open field, Morris Water and Elevated Plus mazes