Myogenic mechanism

Myogenic mechanism

The myogenic mechanism is how arteries and arterioles react to an increase or decrease of blood pressure to keep the blood flow within the blood vessel constant.

The smooth muscle of the blood vessels reacts to the stretching of the muscle by opening ion channels, which cause the muscle to depolarize, leading to muscle contraction. This significantly reduces the volume of blood able to pass through the lumen, which reduces blood flow through the blood vessel. Alternatively when the smooth muscle in the blood vessel relaxes, the ion channels close, resulting in vasodilation of the blood vessel; this increases the rate of flow through the lumen.

This system is especially significant in the kidneys, where the glomerular filtration rate (the rate of blood filtration by the nephron) is particularly sensitive to changes in blood pressure. However, with the aid of the myogenic mechanism, the glomerular filtration rate remains very insensitive to changes in human blood pressure.

External links


v · d · eCardiovascular system, physiology: cardiovascular physiology
Heart
Volumes
Fractional shortening = (End-diastolic dimension – End-systolic dimension) / End-diastolic dimension
Interaction diagrams
Chronotropic (Heart rate) · Dromotropic (Conduction velocity) · Inotropic (Contractility) · Bathmotropic (Excitability) · Lusitropic (Relaxation)
Chamber pressure
Other
Vascular system/
Hemodynamics

M: HRT

anat/phys/devp

noco/cong/tumr, sysi/epon, injr

proc, drug (C1A/1B/1C/1D), blte

M: VAS

anat(a:h/u/t/a/l,v:h/u/t/a/l)/phys/devp/cell/prot

noco/syva/cong/lyvd/tumr, sysi/epon, injr

proc, drug(C2s+n/3/4/5/7/8/9)

Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Myogenic — contraction refers to a myocyte contraction that originates from a property of the myocyte itself. I.e. the contraction is initiated by the cell itself, not an outside occurrence or stimulus such as nerve innervation. Mechanisms Unstable Membrane …   Wikipedia

  • Myogenic contraction — refers to a contraction initiated by the myocyte cell itself instead of an outside occurrence or stimulus such as nerve innervation. Contents 1 Mechanisms 1.1 Unstable Membrane Potentials 1.1.1 Slow wave potentials …   Wikipedia

  • Vasoconstriction — is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, particularly the large arteries, small arterioles and veins. The process is the opposite of vasodilation, the widening of blood vessels. The… …   Wikipedia

  • Cardiac cycle — Cardiac events occurring in the cardiac cycle. Two complete cycles are illustrated. The cardiac cycle is a term referring to all or any of the events related to the flow or blood pressure that occurs from the beginning of one heartbeat to the… …   Wikipedia

  • Jugular venous pressure — A man with congestive heart failure and marked jugular venous distension. External jugular vein marked by an arrow. The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the… …   Wikipedia

  • Pulse — For other uses, see Pulse (disambiguation). Pulse evaluation at the radial artery. In medicine, one s pulse represents the tactile arterial palpation of the heartbeat by trained fingertips. The pulse may be palpated in any place that allows an… …   Wikipedia

  • Blood pressure — For information about high blood pressure, see Hypertension. Blood pressure Diagnostics A sphygmomanometer, a device used for measuring arterial pressure. MeSH …   Wikipedia

  • Circulatory system — This article is about the organ system. For the band, see Circulatory System. For transport in plants, see Vascular tissue. Circulatory system …   Wikipedia

  • Heart sounds — Front of thorax, showing surface relations of bones, lungs (purple), pleura (blue), and heart (red outline). The location of best auscultation for each heart valve are labeled with M , T , A , and P . First heart sound: caused by atrioventricular …   Wikipedia

  • Cardiac output — (Q or or CO ) is the volume of blood being pumped by the heart, in particular by a left or right ventricle in the time interval of one minute. CO may be measured in many ways, for example dm3/min (1 dm3 equals 1000 cm3 or 1 litre). Q is… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”