Myogenic contraction | physiology (2024)

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What is myogenic contraction? ›

A contraction initiated in the muscle itself and not dependent on neural stimulation. The contractions of cardiac muscle cells in the heart are myogenic, although the rhythm of the heartbeat can be modified by neural and hormonal stimulation.

The Journal of Physiology © 2012 The Physiological Society. Myogenic constriction in arterioles is defined as a decrease in vessel diameter in response to increase in blood pressure.

By definition, the myogenic response is the contraction of a blood vessel that occurs when intravascular pressure is elevated and, conversely, the vasodilation that follows a reduction in pressure.

The myogenic response involves stretch activation of mechanosensitive ion channels resulting in depolarization of VSM cells and calcium influx through L-type voltage-gated calcium channels (VGCC), Ca²⁺/calmodulin-dependent phosphorylation of myosin light chain kinase and sensitization of actinomyosin-based contractile ...

Myogenic contractures involving muscle, fascia, and tendon produced muscle atrophy and are the main etiology of a limited range of joint motion when a joint is immobilized for two weeks [13,15,29, 48] . Arthrogenic contractures, due to articular cartilage and periarticular structures, occur after four weeks [13]. ...

1. : originating in muscle. myogenic pain. 2. : taking place or functioning in ordered rhythmic fashion because of inherent properties of cardiac muscle rather than by reason of specific neural stimuli.

Myogenic activity refers to the ability of a muscle to contract reflexively without nervous stimulation. Smooth and cardiac muscle both possess myogenic activity. Both the muscles are involuntary muscles. Skeletal muscles are closely associated with skeletal components in the human body.

The Myogenic Response Arises from the Contractile Response to Stretch. William Bayliss discovered the myogenic response in 1902 when he found that distension of blood vessels by increased blood pressure caused their contraction. Thus, the myogenic response results from stretch-induced contraction.

Myogenic: ​A characteristic of cardiac muscle where it can initiate its own contractions without the need for nervous stimulation. Purkyne fibres: ​Bundles of heart muscle cells carry the electrical impulse from the bundles of His upwards through the ventricles which causes contraction from the bottom up.

The SA node has the inherent power of generating a wave of contraction and controlling the heartbeat. Hence, it is known as the pacemaker. Since the heartbeat is initiated by the SA node and the impulse of contraction originates in the heart itself, the human heart is termed myogenic.

What is the myogenic process? ›

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.

The myogenic mechanism refers to the reflex response of the afferent arterioles, where changes in blood pressure cause the vascular smooth muscle to contract or relax. This mechanism protects the glomerulus from damage by high pressure and helps regulate the glomerular filtration rate.

Mitogenesis is the induction (triggering) of mitosis, typically via a mitogen. The mechanism of action of a mitogen is that it triggers signal transduction pathways involving mitogen-activated protein kinase (MAPK), leading to mitosis.

Local myogenic contraction (spasm) which is initiated by direct damage to the wall of the blood vessel. Local humoral factors from the damaged tissues and the platelets (for example, thromboxane A and serotonin)

The myogenic behavior of resistance arteries and arterioles involves two phenomenon: myogenic tone, which is a state of partial constriction at a constant pressure, and myogenic reactivity, which is the alteration in tone in response to a change in pressure [71] (Figure 11).

The hearts of other invertebrates exhibit this neurogenic contraction. … heart rhythm may be either myogenic (originating within the heart muscle itself) or neurogenic (originating in nerve ganglia).