Neonatal vitamin E treatment induces long term glucocorticoid receptor changes: an unusual hormonal imprinting effect.

Single neonatal vitamin E treatment significantly altered the affinity (Kd) of thymic glucocorticoid receptors in male adolescent and adult rats. In six weeks old animals the affinity increased (and there is a tendency for an increase in receptor density), in twelve weeks old animals the affinity decreased. The thymic glucocorticoid receptors and uterine estrogen receptors of female animals were not influenced at all. Thousandfold tocopherol did not compete with labeled dexamethasone for their receptors, suggesting that neonatal vitamin E imprinting effect was not done at direct receptorial level.