Is vasopressin an important XXXX hormone?

@entity1831 @entity1369 @entity101 @entity5463 @entity235
To generate quantitative data relating to the potential @entity101 activity of @entity5463 ( @entity1831 ), 140 and 560 microunits @entity1831 /kg/min were infused chronically in both normotensive @entity235 and @entity235 made @entity101 by chronic infusion of either angiotensin II (AII) or @entity1369 . The lower rate of @entity1831 infusion increased plasma @entity1831 concentration from 0.4 +/- 0.1 microunits/ml. Mean arterial pressure (MAP) was recorded 24 hours per day, and all @entity235 were infused continuously with 800 ml of isotonic saline per day. During the initial days of @entity1831 infusion in normotensive @entity235 , natriuresis, kaliuresis, and water retention were prominent and MAP increased progressively to a peak on Day 6 (30 mm Hg above control). Subsequently, diuresis ensued, net water retention decreased, and MAP fell progressively to only 13 mm Hg above control by Day 12 of @entity1831 infusion. In contrast, in AII or @entity1369 @entity101 @entity235 during @entity1831 infusion, the natriuresis was greatly attenuated, water balance was unchanged or even negative, and MAP either did not increase or increased only transiently. When @entity1831 infusion was terminated in @entity235 given only @entity1831 , diuresis occurred, and MAP fell gradually over a period of hours to @entity101 levels. In marked contrast, cessation of @entity1831 infusion in @entity235 with either AII or @entity1369 @entity101 was associated with a precipitous fall in MAP of 35 to 40 mm Hg within 1 hour: however, this reduction was only transient - over the subsequent hours, both salt and water retention occurred, and MAP returned to previous @entity101 levels. Thus, in the @entity101 models studied, high plasma levels of @entity1831 had relatively weak @entity101 effects. Although variations in plasma @entity1831 concentration were associated with rather pronounced acute effects on MAP, the long-term changes in MAP produced by @entity1831 were either minimal or, in the case of the animals made @entity101 by other agents, nonexistent.
