Effects of ingestion of radioactive cesium on behavioral indices in rats.

The experiments were carried out on 35 male (M) and female (F) rats contaminated by ingestion of Cesium--137(Cs) for 38 or 84 days; the total Cs activity was 288 Bq 460 Bq, and respectively. The duration of forced swimming decreased significantly in the contaminated groups as compared with controls (n = 16). The active avoidance reaction in the shuttle-box shows an increase in F groups and a decrease in M groups. The total latency time of the same reaction was lower in F and M treated rats on the first day of learning. The score of aggressive behavior rose significantly, especially in group F. These results can be explained by the sex dependence of Cs accumulation and by the neurotoxic action of the radionuclide on several central neural areas including monoaminergic and endocrine mechanisms.