Edit page | Page history | Printable version

smooth muscle

(Science: anatomy, pathology, physiology) 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 (particularly the gizzard in birds) and in the uterus.

The contractile system and its control resemble those of motile tissue cells (e.g. 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. A muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart).Muscle tissue that does not appear striated under the microscope; has the form of thin layers or sheets.A muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart).Another term for involuntary muscle, see [[involuntary muscle.