To further characterize the role of rasopressin in DOC-salt hypertension, four groups of unilaterally nephrectomized rats were studied: control rats giren no further treatment, rats treated with DOC and giren 1% saline to drink, or rats treated with only DOC, or 1% saline. Only rats treated with DOC or DOCsalt became hypertensive. Control rats and rats treated with only DOC or 1% saline had similar pressor responses to exogenous rasopressin and angiotensin II. Within the DOC-salt group, two populations of rats were identified: one with normal pressor responsiveness to rasopressin, and one with markedly enhanced pressor responsireness to rasopressin. Incidence of enhanced responsiveness increased with duration of treatment. Urinary excretion of rasopressin was elerated in the 1% saline and DOC-salt groups after 1 week of treatment, and in the DOC group after 4 weeks. Howerer, the plasma rasopressin concentration was elerated only in the rats treated with both DOC and saline. It is suggested that rasopressin is essential for the expansion of blood rolume in the early stages of DOC-salt hypertension, and functions as a direct pressor agent only in the later stages.
|Original language||English (US)|
|Number of pages||9|
|State||Published - Jan 1 1980|
- DOC-salt hypertension
- Pressor responsireness
ASJC Scopus subject areas
- Internal Medicine