Orthostatic reaction

Orthostatic reaction is the organism's reflex reaction to orthostatic hypotension - a decrease in blood pressure due to the change in position from lying down to standing. It is mediated by the baroreflex. A decrease in blood pressure causes a decrease in the activity of baroreceptors in the sinus caroticus and arcus aortae, which leads to parasympathetic inhibition and a decrease in sympathetic inhibition. This results in vasoconstriction, increased heart rate and contractility. ==Links==

Related articles
===Bibliography ===
 * Baroreflex
 * Blood pressure regulation