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The muscular system is an organ system consisting of skeletal, smooth, and cardiac muscle. It permits movement of the body, maintains posture, and circulates blood throughout the body. [ 1 ] The muscular systems in vertebrates are controlled through the nervous system although some muscles (such as the cardiac muscle ) can be completely autonomous.
This is called the precapillary sphincter. The precapillary sphincter has now also been found in the brain, where it regulates blood flow to the capillary bed. [3] The sphincter can open and close the entrance to the capillary, by which contraction causes blood flow in a capillary to change as vasomotion occurs. [4] [unreliable source?
Often expressed in cm/s. This value is inversely related to the total cross-sectional area of the blood vessel and also differs per cross-section, because in normal condition the blood flow has laminar characteristics. For this reason, the blood flow velocity is the fastest in the middle of the vessel and slowest at the vessel wall.
These cells control whether the vessels are constricted or dilated, which dictates the amount of oxygen and glucose that is able to reach the neuronal tissue. Brain blood vasculature as a function of blood flow. Red arrows show vascular pruning, while white arrowheads indicate vessel widening in response to increased blood flow. [3]
Below are several examples of differing types of local blood flow regulation by specific organ type or organ system. In each case, there is a specific type of intrinsic regulation occurring in order to maintain or alter blood flow to that given organ alone, instead of creating a systemic change that would affect the entire body.
Smooth muscles are used to control the flow of substances within the lumens of hollow organs, and are not consciously controlled. Skeletal and cardiac muscles have striations that are visible under a microscope due to the components within their cells. Only skeletal and smooth muscles are part of the musculoskeletal system and only the muscles ...
The skeletal muscle pump or musculovenous pump is a collection of skeletal muscles that aid the heart in the circulation of blood. It is especially important in increasing venous return to the heart, [1] but may also play a role in arterial blood flow.
The myogenic mechanism is how arteries and arterioles react to an increase or decrease of blood pressure to keep the blood flow constant within the blood vessel.Myogenic response refers to a contraction initiated by the myocyte itself instead of an outside occurrence or stimulus such as nerve innervation.