Hereditary diabetes insipidus in rats. Altered cerebral indolamine and catecholamine metabolism.

Compared to heterozygous Brattleboro animals, homozygous (diabetes insipidus) rats exhibited higher steady-state levels of serotonin in the mesencephalon, septum and striatum. These differences disappeared upon the administration of pargyline, suggesting accumulation of serotonin. The norepinephrine level was higher in the mesencephalon, while the disappearance rate (alpha-met hyl-p-tyrosine) was accelerated in the septum and decreased in the hypothalamus. The lower striatal dopamine level was associated with a decreased disappearance rate. The data suggest that the altered monoamine metabolism might be associated with the known endocrine and behavioral disturbances of the homozygous rats.