Effects of ingestion of organic selenium in adapted and non-adapted rats

1. Rats were given moderate-selenium (4-5 mg/kg) or low-Se (0-5 mg/kg) diets during gestation and lactation. Their young were given diets with high (10 mg/kg), moderate or low Se contents from weaning, and groups of rats were killed at intervals during the 14-week experimental peroid. 2. Compared with young rats which received the low-Se diet, those which received the moderate- or high-Se diets had a high incidence of liver lesions and there were changes in liver Se content, haemoglobin concentration, packed cell volume, prothrombin activity, fibrinogen content, spleen weight, body water and serum glutamic-oxaloacetic and glutamic-pyruvic transaminas (L-aspartate : 2-oxoglutarate aminotransferase; EC 2.6.1.1 and L-alanine : 2-oxoglutarate aminotransferase; EC 2.6.1.2 respectively) and alkaline phosphatase (EC 3.1.3.1) activities. In those rats which received the high-Se diet the changes were more pronounced than in those which received the moderate-Se diet. 3. In young rats from dams given moderate-Se diets, which were themselves given the moderate-Se diet, the liver Se content decreased continuously, whereas rats given the same diet but from dams which had received the low-Se diet, the liver Se content increased continuously. There was a slight improvement of symptoms of Se toxicity in all groups by the 5th week of the experimental peroid. 4. The results suggest that there was an adaptation to chronic Se intake.