Mean Arterial Pressure (MAP) is sensed by baroreceptors in various parts of the body. Describe the body’s short-term and long-term responses to a drop in MAP.

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bandmanjoe eNotes educator| Certified Educator

The mean arterial pressure is the average blood pressure within the arterial walls of a persons circulatory system.  Organs must receive blood to deliver nutrients and oxygen and also to pick up carbon dioxide and other waste products that are produced as a byproduct of cellular respiration.  Organs can continue to function on a mean arterial pressure as low as 60 millimeters of mercury.  The average mean arterial pressure is somewhere between 70 to 110 millimeters of mercury.  The short-term response by the body when experiencing a drop in mean arterial pressure would be an increased heart rate, in an effort to rebuild the drop in pressure.  Blood vessels could also constrict, causing a rise in blood pressure.  The long-term responses of the body could be increased levels of epinephrine, which would increase the heart rate, and other hormones which would cause the blood pressure to increase.