Vasopressin escape and memory impairment in a model of chronic syndrome of inappropriate secretion of antidiuretic hormone in mice

Recently, chronic hyponatremia, even mild, has shown to be associated with poor quality of life and high mortality. The mechanism by which hyponatremia contributes those symptoms, however, remains elucidated. Syndrome inappropriate secretion antidiuretic hormone (SIADH) is a primary cause hyponatremia. Appropriate animal models are crucial for investigating the pathophysiology SIADH. A rat model SIADH been generally used mouse have rarely used. In this study, we developed in stable sustained occurred after 3-week continuous infusion vasopressin V2 receptor agonist 1-desamino-8-D-arginine (dDAVP) liquid diet feeding produce water loading. Weight gain mice at week 2 3 starting dDAVP injection was similar that control mice, suggesting animals adapted grew up normally. AQP2 expression kidney, reflects renal action vasopressin, decreased dDAVP-infused water-loaded as compared received same but were fed pelleted chow. These results suggest “vasopressin escape” occurred, an important process limiting potentially fatal severe Behavioral analyses using contextual cued fear conditioning test T-maze demonstrated cognitive impairment, especially working memory partially restored correcting Our escape contributed their impairment.