Flood Stage. 1  The term stage refers to the height of a river (or any other body of water) above a locally defined elevation. This locally defined elevation is a reference level, often referred to as datum. 2  When the discharge of a river increases, the channel may become completely full.
vasoconstrictor (vÄÂ´zÅkÉnstrikÂ´tur) , n (vasopressor), an agent that causes a rise in blood pressure by constricting the blood vessels. In local areas, it causes constriction of the arterioles and capillaries. Vasoconstrictor agents. 2  vasoconstrictor center. 3  vasoconstrictor center. 4  vasoconstrictor center. 5  vasoconstrictor center. 6  vasoconstrictor fibers. 7  vasoconstrictor fibers. 8  vasoconstrictor fibers. 9  vasoconstrictor nerve. 10  vasoconstrictor nerve.
Vasoconstriction. One of the first effects is intense vasoconstriction of the skin vessels over the entire body. The posterior hypothalamus strongly activates the sympathetic nervous signals to the skin blood vessels, and intense vasoconstriction occurs throughout the body.