Blood Pressure Homeostasis
Homeostasis in the ability of the body to keep an internal environment that is constant, regardless of outside influences. Blood pressure remains within normal limits through the utilization of both rapid and slow mechanisms. Working together, the mechanisms strive to maintain an approximate blood pressure of 120/80 mm Hg. The baroreceptor reflex is one of the most important fast acting homeostatic mechanisms involved in regulating blood pressure. This contains receptors, sensory nerves, and the medulla oblongata and motor nerves, all working together. Another rapid acting mechanism in the regulation of blood pressure is the secretion of epinephrine and norepinephrine by the adrenal gland.
Baroreceptors, are found in certain places in the walls of the heart where they are able to sense any change in blood pressure. After the baroreceptor sence a change the sensory nerves are activated and send a ...view middle of the document...
The sympathetic nervous system also causes some blood vessels to constrict, which increases the resistance of the vessels. Together, these responses increase the amount of blood pumped by the heart each minute, which increases the blood pressure.
If blood pressure is too high and a decrease in blood pressure is needed, the parasympathetic nervous system comes into play. The parasympathetic nerves cause blood vessels to open, which decreases resistance, and causes blood to drop pressure. The body is constantly trying to keep blood pressure at a healthy rang, and makes adjustments when necessary.
As we age our bodies start to change not only on the outside, but also on the inside. Our hearts of instance start to change as we age. The heart walls particularly the left ventricle, get thicker, heart muscles start to get weaker, abnormal heart rhythms becomes more common, and heart valves become thicker or start to leak. Age-related heart changes may decrease the heart’s ability to pump blood as efficiently, making the heart less able to stand increased workloads. Coronary artery disease, congestive heart failure, and myocardial infarction are some heart problems you have to worry about when aging.
Coronary artery disease is a result of plaque buildup in your coronary arteries -- a condition called atherosclerosis -- that leads to blockages. The arteries, which start out smooth and elastic, become narrow and rigid, restricting blood flow to the heart. The heart becomes starved of oxygen and the vital nutrients it needs to pump properly.
Congestive heart failure occurs when your heart muscle doesn't pump blood as well as it should. Certain conditions, such as narrowed arteries in your heart (coronary artery disease) or high blood pressure, gradually leave your heart too weak or stiff to fill and pump efficiently.
Myocardial infarction also known a heart attack happens when a portion of the heart muscle (myocardium) is damaged because of sudden obstruction of one of the coronary arteries that supply the oxygen rich blood to the heart muscle.
As we age we are more susceptible to these disease of the heart because our hearts are becoming more weak and fragile. It is important to watch out for these as we age.