Selenium in the testis of the rat: studies on its regulation and its importance for the organism.

In male rats, fed for 10 weeks on a Torula yeast-based, low selenium and low vitamin E diet, the selenium level and the glutathione peroxidase activity in the blood and in several tissues decreased by 50 to 98% compared with animals that received the same basal diet supplemented with 0.25 mg Se/kg sodium selenite. In the testes, however, the selenium content did not differ from that of the control animals. Despite the low selenium levels in the extragonadal tissues and their increased requirement of this element due to the low vitamin E status, the selenium from an intravenously injected dose of sodium selenite was retained above all in the testes. After the removal of the pituitary gland, because of the decrease in the testicular mass and in the selenium content in the remaining testicular tissue, the amount of selenium in the testes was greatly reduced. After administration of pregnant mare's serum gonadotropin (PMS), due to the regeneration of the tissue and the simultaneous restoration of the selenium content, a relatively large amount of this element was shifted to the testes even though the selenium status in the other tissues was low. The results of these studies show that the selenium level in the male gonads is maintained by regulation mechanisms and that the supply of sufficient amounts of selenium to the testes has priority over the supply to other tissues.