The problem presented on this study will deal on the happening from the standpoint of the cardiovascular system when there is drop in blood pressure as portrayed by Susie when she took a bath and passed out when she stood up. What long term mechanisms will the body utilize in order to maintain a normal blood pressure range? This research will try to explain all body systems that are integral components to blood pressure homeostasis.
Homeostasis is a state of equilibrium or a tendency to reach equilibrium, either metabolically within a cell or organism or socially and psychologically within an individual or group (Encarta Dictionary – 2009). Homoeostasis is not a living thing but rather it is the capability of the physique in maintaining a steady state in organisms (Flint, Devanda – March 7, 2012 – “Homeostasis & Blood Pressure” – eHow Health). The body constantly controls its internal environment despite outside influences. Using various internal mechanisms are used by the body to keep constant control of blood pressure, respiration, temperature and blood glucose measures (Celli,Beth – eHow Health).
Blood pressure remains in normal limits with the use of rapid or slow mechanisms as the need arises. By working together, its mechanisms will attempt to maintain approximately 120/80 mm Hg. Blood pressure (Celli). Once the temperature rise above its normal range, the reflexes interacts to bring back its steady state hence the body reacts when there is perspiration and reduced metabolism. Persistent deviation is initiated by the body to do actions such as taking cover when it’s hot or go for a swimming to keep the body temperature return to normal. Other corrective interactions of the system are also observed following this pattern such as blood glucose level, osmotic pressure and blood pH. These are the usual procedure in homeostasis. Below normal range, there is a sensory input which reports the changes in steady state and effect mechanisms to restore it steady state (International Encyclopedia of the Social Sciences).
One of vital fast homeostatic mechanisms that are involved to regulate blood pressure is called baroreceptor reflex. This is received by receptors working together from the sensory nerves to medulla oblongata as well as the motor nerves. Another rapid mechanism in regulating blood pressure is the adrenal gland in which epinephrine and norepinephrine hormones are secreted. Both of which tend to intensify the volume of blood being pumped by the heart per minute thereby causing the blood vessels to contract. These reactions will help the blood pressure to escalate. This simply means that the sensory nerves activates when sudden changes are notices by baroreceptors. These receptors that are found on the heart walling are activated when baroreceptors notice some changes through medulla oblongata where the message is being interpreted. When the signal is received, the medulla decides to increase or lower the blood pressure. The needed adjustment to stabilize blood pressure is activated by autonomic nervous system through the motor nerves.
The autonomic nervous system comprises Sympathetic Nervous System and Parasympathetic Nervous System. Each has their own functions. If blood pressure needs to be increased, the sympathetic nervous system do the work which causes some of the blood vessels to narrow down and increase the volume of blood pumped thereby increasing the blood pressure. If the blood pressure needs to be decreased, the parasympathetic nervous system is signaled by medulla oblongata to lower the blood pressure. The parasympathetic nerves will make the blood vessels either to expand or open to decrease resistance leading to lessen blood pressure.There are also mechanisms which deal with long-term limitation of blood pressure. The most relevant mechanism is the rennin-angiotension-aldosterone. The kidneys are responsible for the secretion of renin and aldosterone going to the bloodstream which causes the constriction of blood vessels. Aldosterone will tend to increase the volume of water and sodium that are being immersed by the kidneys leading to the increase of blood as well as water into the bloodstream. This joint activity will cause the increase of blood pressure (eHow Health).
Therefore, a feedback mechanism often gets involved to maintain homeostasis. The body no longer signals the other internal systems once the breathing rate becomes normal again (1997 McGraw-Hill College Division – “Body System and Homeostasis”).