Autoimmune alterations in the neurohypophysis of rabbits immunized against vasopressin.

Rabbits immunized against vasopressin developed clinical signs of diabetes insipidus persisting for up to two months after the last boost. Ultrastructural and immunocytochemical studies of the neurohypophysis demonstrated autoimmune alterations: infiltration by immune cells and extracellular deposits of immunoglobulins. No alterations were observed in the hypothalamic nuclei synthesizing vasopressin nor in hormone-target cells of the kidney. Immunization against vasopressin may provide the first example of an autoimmune disease in the hypothalamo-neurohypophysial system.