Effects of vitamin E and selenium deficiencies on rat capillaries.

Capillaries in the retina and rectus muscles of vitamin E and selenium deficient rats were examined by electron microscopy. In vitamin E deficient rats, retinal capillaries showed thickening of the basement membranes of the endothelial cells. On the other hand, capillaries in the muscles had thin basement membranes, and hemorrhages occurred due to the breakdown of endothelial cells. In selenium-deficient rats no significant abnormalities were seen in retinal or muscle capillaries. Although selenium has been considered to be similar to vitamin E as an antioxidant, the present study suggests that they are different. The effect of vitamin E on capillary basement membranes varies from tissue to tissue.