Lexic.us

Definition of Heart muscle

1. Noun. The muscle tissue of the heart; adapted to continued rhythmic contraction.

Medical Definition of Heart muscle

1. Tissue specialised for contraction. See twitch muscle, catch muscle: Cardiac muscle (heart muscle) is a striated but involuntary muscle responsible for the pumping activity of the vertebrate heart. The individual muscle cells are joined through a junctional complex known as the intercalated disc and are not fused together into multinucleate structures as they are in skeletal muscle. Skeletal muscle is a rather non-specific term usually applied to the striated muscle of vertebrates that is under voluntary control. The muscle fibres are syncytial and contain myofibrils, tandem arrays of sarcomeres. Smooth muscle is muscle tissue in vertebrates made up from long tapering cells that may be anything from 20-500m long. Smooth muscle is generally involuntary and differs from striated muscle in the much higher actin/myosin ratio, the absence of conspicuous sarcomeres and the ability to contract to a much smaller fraction of its resting length. Smooth muscle cells are found particularly in blood vessel walls, surrounding the intestine (especially the gizzard in birds) and in the uterus. The contractile system and its control resemble those of motile tissue cells (for example fibroblasts, leucocytes) and antibodies against smooth muscle myosin will cross react with myosin from tissue cells, whereas antibodies against skeletal muscle myosin will not. See: dense bodies. This entry appears with permission from the Dictionary of Cell and Molecular Biology (11 Mar 2008)

Lexicographical Neighbors of Heart Muscle

Literary usage of Heart muscle

Below you will find example usage of this term as found in modern and/or classical literature:

1. A Text-book of physiology: For Medical Students and Physicians by William Henry Howell (1915)
"The Tonicity of the heart muscle.—In describing the physiology of skeletal and plain ... So in the heart muscle the power to maintain a certain degree of ..."

2. The Principles and Practice of Medicine: Designed for the Use of by William Osler (1912)
"But in spite of this enormous call for force, insufficiency of the heart muscle does not necessarily result, for the working force required is ..."

3. The American Journal of the Medical Sciences by Southern Society for Clinical Investigation (U.S.) (1911)
"In proof of this it has been demonstrated by Englemann that by artificial stimulation a contraction wave may be induced in any part of the heart muscle. ..."

4. Science by American Association for the Advancement of Science (1904)
"Before the action of these drugs on the ganglion and the heart muscle of ... The heart-muscle responds to the stimulation of the nerves that pass from the ..."

5. The Medical Clinics of North America by Richard J. Havel, K. Patrick Ober (1919)
"The important thing is what the patient can do, and this depends largely on the quality of the heart muscle. Given as strong a heart muscle as this man must ..."

6. Principles of General Physiology by William Maddock Bayliss (1920)
"This can easily be detected in the heart muscle. If a stimulus is put in at various points 011 the course of a previous contraction, natural or excited by ..."

7. Diseases of the heart by James Mackenzie (1908)
"Characteristics of the functions of the heart muscle-fibres. § 8. Myogenic doctrine—While it would be somewhat beyond my province to enter into a discussion ..."

Other Resources: