Introduction[edit | edit source]
Arteries make up a major part of the circulatory system, with the veins and heart being the other main components (all the blood vessels’ combined length is close to 93300 kilometers). Arteries are composed of smooth muscle allowing constriction and dilation through the parasympathetic nervous system. Arteries are deep under the skin. They do not have valves to prevent blood from flowing backwards. Instead, every time the heart beats, the arteries stretch out so the blood has room to go through. Once the walls have completely stretched out, the muscles in the arteries make them shrink back to their normal size. This pushes the blood through.
- Systemic arteries carry blood away from the heart, transporting oxygenated blood from the left ventricle to and from every organ in the body. Blood is pumped from the ventricles into large elastic arteries that branch repeatedly into smaller and smaller arteries until the branching results in microscopic arterioles. The arterioles play a key role in regulating blood flow into the tissue capillaries. About 12 percent of the total blood volume is in the systemic arterial system at any given time (60 % veins, 7%arterioles and capillaries) .
- Pulmonary arteries transport blood that has a low oxygen content from the right ventricle to the lungs.
Function[edit | edit source]
- Arteries can dispense fresh oxygen to the body after it gets loaded onto the Fe 2+ found in the center of hemoglobin. The oxygen binds to hemoglobin and is carried by the arteries to areas that are lacking oxygen. Through a shift in affinity for the oxygen, it is then unloaded to specific areas through high surface areas knowns as capillaries.
- Far from being a changeless structure, arteries adapt through signals received from the central nervous system, as they also react to an outer stimulus like pressure, temperature, and substances.
- Vascular nerves are responsible for innervating the arteries allowing them to change to their stimuli. As catecholamines get released into the blood, the nerves send signals to the arteries to either constrict or dilate, leading to changes in pressure
- Arteries in the systemic circulation can be divided into muscular or elastic depending on the type of tissue in the middle section of the artery. Larger arteries tend to be elastic and smaller ones are muscular. The latter are the one that deliver blood to the arterioles.
Structure[edit | edit source]
The arteries throughout the body are composed of three different layers.
- The most inner layer is the tunica intima: Made up of a smooth muscle layer that contains one layer of endothelial cells, and the rest is smooth muscle and elastin; creates a tube for the oxygen-rich blood to move through to reach the appropriate site of perfusion ( ensuring there is no leakage from the artery, and the nutrient-rich blood can move to the appropriate area before it unloads its oxygen and other nutrients).
- The second layer is known as the Media or the middle layer: Made up of more smooth muscle that can dilate or constrict, which adjusts the pressures on the arterial walls during systolic pumping. This layer of muscle lets arteries handle the high pressures from the heart.
- The outermost layer known as the Adventitia: Connective tissue anchoring arteries to nearby tissues. Crucial for connecting the arteries to other tissues in the body, including the vascular nerves, which control the smooth muscles in the arteries.
The largest artery is the aorta, the main high-pressure pipeline connected to the heart's left ventricle. The aorta branches into a network of smaller arteries that extend throughout the body. The arteries' smaller branches are called arterioles and capillaries. The pulmonary arteries carry oxygen-poor blood from the heart to the lungs under low pressure, making these arteries unique.
Disease[edit | edit source]
Arteries play a crucial role in maintaining homeostasis in the body.
As individuals age, health issues begin presenting themselves in the form of stiffening or thicking of the arteries; however, many different issues develop with age and poor diet eg arteries begin to clog with a thicking of plaque known as atherosclerosis. As problems arise in the structure of the arteries, it begins leading to more strain on the heart, which develops congestive heart failure and which is often fatal. The arteries are vital to maintaining a healthy cardiovascular system. In unhealthy arteries the Arterial diseases listed below may arise as a consequence.
- Abdominal Aortic Aneurysm
- Thoracic Aortic Aneurysm
- Coronary Artery Disease
- Carotid Artery Disease
- Peripheral Arterial Disease
- Vertebrobasilar Disease
- Renal Vascular Disease
- Thoracic Outlet Syndrome
- Subclavian Steal Syndrome
Physiotherapy[edit | edit source]
Promotion of Physical Activity
A regular exercise program has a major effect on the health of arteries. Doctors used to think of arteries as passive conduits for blood. Wrong. Arteries are complex structures with crucial regulatory functions, and they are in the front line of the battle for cardiovascular health.
- A sedentary lifestyle is one of the 5 major risk factors (along with high blood pressure, abnormal values for blood lipids, smoking, and obesity) for cardiovascular disease.
- Exercising muscles need more blood. And in response to regular exercise, they actually grow more blood vessels by expanding the network of capillaries. In turn, muscle cells boost levels of the enzymes that allow them to use oxygen to generate energy ie More oxygen-rich blood and more efficient metabolism: It's the formula that explains why people who exercise regularly enhance their endurance and strength.
- There is evidence that exercise training improves the capacity of the blood vessels to dilate in response to exercise or hormones, consistent with better vascular wall function and an improved ability to provide oxygen to the muscles during exercise.
- Regular exercise helps arteries by boosting the endothelial cells' nitric oxide production. This nitric oxide has two crucial functions. It keeps the arterial lining smooth and slippery, preventing white blood cells and platelets from latching on and causing damaging inflammation and artery-blocking blood clots. In addition, it relaxes the smooth muscle cells of the artery wall's middle layer, preventing spasms and keeping arteries open.
References[edit | edit source]
- Easy science for kids Arteries Available:https://easyscienceforkids.com/the-veins-and-arteries-of-the-circulatory-system-video-for-kids/ (accessed 14.7.2021)
- Mercadante AA, Raja A. Anatomy, Arteries. [Updated 2021 Jan 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Available:https://www.ncbi.nlm.nih.gov/books/NBK547743/ (accessed 14.7.2021)
- Kids search Artery Available:https://kids.kiddle.co/Artery (accessed 14.7.2021)
- Wolff, Christopher & Collier, David & M, Shah & Saxena, Manish & TJ, Brier & Kapil, Vikas & Green, David & Lobo, Melvin. (2016). A Discussion on the Regulation of Blood Flow and Pressure.. Advances in Experimental Medicine and Biology. 129-135. 10.1007/978-1-4939-3023-4_16..Available: https://www.researchgate.net/publication/291522547_A_Discussion_on_the_Regulation_of_Blood_Flow_and_Pressure/citation/download (accessed 14.7.2021)
- NIH Blood Vessels Available: https://training.seer.cancer.gov/anatomy/cardiovascular/blood/classification.html (accessed 14.7.2021)
- Medical stock images Facts about arteries Available:https://www.medicalstockimages.net/blogs/news/facts-about-the-human-arteries (accessed 14.7.2021)
- Web MD Arteries Available:https://www.webmd.com/heart/picture-of-the-arteries#1(accessed 14.7.2021)
- Michigan Medicine Artery Disease Available:https://www.umcvc.org/conditions-treatments/arterial-artery-disease (accessed 14.7.2021)
- Exercise and Cardiovascular Health Jonathan Myers Originally published7 Jan 2003 Circulation. 2003;107:e2–e5 Available :https://www.ahajournals.org/doi/full/10.1161/01.CIR.0000048890.59383.8D (accessed 15.7.2021)
- Harvard Health Exercise and your Arteries Available: https://www.health.harvard.edu/heart-health/exercise-and-your-arteries (accessed 15.7.2021)