Study on the biological half-life and organ-distribution of tritiated lysine-vasopressin in Brattleboro rats.

The biological half-life and organ-distribution of triated lysine-vasopressin were determined in R-Amsterdam rats, and in homozygous and heterozygous Braddleboro rats with hereditary central diabetes insipidus. It was found that the biological half-life of the tritiated lysin-vasopressin in the Brattleboro rats did not differ significantly from that found in the R-Amsterdam rats. The highest radioactivities were observed in the neuro- and adenohypophyses and in the kidneys of both the R-Amsterdam and the Brattleboro rats. The accumulation of tritiated LVP was higher in the small intestine of the Brattleboro rats than in that of the R-Amsterdam animals. The results have led to the conclusion that the accelerated elimination of vasopressin and its pathologic organ-accumulation are probably not involved in the water metabolism disturbance of Brattleboro rats with hereditary hypothalamic diabetes insipidus.