As you know, all the muscle cells have common features.But even the average medical student is easy to distinguish the different types of cell samples.Smooth muscle tissue has characteristic differences.And if you have at least minimal knowledge, you will never confuse the striated and smooth muscles.It's simple enough.In this article we will talk about what is the smooth muscle tissue, and more about its properties and structure.
main feature that distinguishes this type of muscle tissue from the tissue, which is driven by the human mind (arbitrary), - the lack of cross-striations.In one cell there is only one single core, located near the middle of it (the same line is the heart muscle).It is you and you will see under the microscope slide.
For the most part smooth muscle tissue located in the walls of hollow organs of various systems, as well as a part of the vessel wall.If this tissue is located in the wall of the organ, it usually forms two layers.Internal - ring and an outer - longitudinal.However, in some parts of the various systems is typically broken and the fibers are arranged spirally, for example, in large arteries.Only at the level of arterioles human muscle fibers are arranged in a ring.
smooth layers of fabric types are divided into bundles of fibers, each of which is surrounded by connective tissue, through which the muscle cells are suitable for the nerves and blood vials.The beams are intertwined with each other, and therefore formed a kind of integrated network of muscle fibers, which carry out their work together.
Smooth muscle tissue like muscles and heart, are the responsibility of the autonomic nervous system, and therefore its operation not subject to conscious control.This fabric is capable of for a long time in a state of partial contraction (to maintain the tone).Therefore, the tubular structure capable of a long time to have a certain clearance.It is very important for such a measure as a relatively constant blood pressure.
If the tone increases, the lumen can be narrowed.Sometimes it is pathological.For example, when a person suffers from asthma, smooth muscle tone smallest bronchi becomes excessive, and the air can not circulate properly.The same process, according to some sources, is the basis of formation of hypertension in humans.
Smooth muscle tissue is also able to adjust the amount of elastin in blood vessels.In the walls of the gastrointestinal tract, ureters and oviducts smooth muscles contract rhythmically, forming the so-called peristaltic waves which run through tubes and push their contents in the right direction.
Compared striated and smooth muscle cells, it may be noted that smooth declining much more slowly.Exception - smooth structure of the pupil who instantly react to light.
As you know, in the muscle tissue contains proteins actin and myosin.It was found that the actin smooth muscle cells ahead striated.Also, studies using greatly increased microscopes revealed that the sarcoplasmic reticulum in smooth muscle cells is less developed than in the striated.
As we saw above, there are two types of this species tissue.Cells of the first, which is a part of, can be reduced very slowly.This type is called visceral.But the smooth muscle tissue in the structure of the sphincter of the pupil that can be reduced quickly, called muscle tissue innervation to the individual fibers.As the name of the second, where each fiber has its nerve.The first type of costs body "cheaper" - a nervous process there has been a variety of fibers.
More on smooth muscle tissue can be found in textbooks of histology.But to the layman the information in this article should be enough.
