Search results
Results from the WOW.Com Content Network
T-tubules (transverse tubules) are extensions of the cell membrane that penetrate into the center of skeletal and cardiac muscle cells.With membranes that contain large concentrations of ion channels, transporters, and pumps, T-tubules permit rapid transmission of the action potential into the cell, and also play an important role in regulating cellular calcium concentration.
Troponin C, also known as TN-C or TnC, is a protein that resides in the troponin complex on actin thin filaments of striated muscle (cardiac, fast-twitch skeletal, or slow-twitch skeletal) and is responsible for binding calcium to activate muscle contraction.
The expression of cTnT in skeletal tissue of patients with chronic skeletal muscle injuries has been described. [12] Inside the cardiac troponin complex the strongest interaction between molecules has been demonstrated for cTnI – TnC binary complex especially in the presence of Ca 2+ ( KA = 1.5 × 10 −8 M −1). [13]
These studies have been extended to a number of cell types with similar results. Extensive studies in neuronal cells, [21] fibroblasts, [16] [17] [22] skeletal muscle [23] [24] and osteoclast cells has further highlighted the complex association tropomyosin isoforms have with cellular structures. These studies have led to the realization that ...
When blood pressure is increased in the blood vessels and the blood vessels distend, they react with a constriction; this is the Bayliss effect. Stretch of the muscle membrane opens a stretch-activated ion channel. The cells then become depolarized and this results in a Ca 2+ signal and triggers muscle contraction. No action potential is ...
Depiction of smooth muscle contraction. Muscle contraction is the activation of tension-generating sites within muscle cells. [1] [2] In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. [1]
Firstly, it binds to the intracellular side of the DHPR, signalling the channels to close and preventing further influx of Ca 2+ into the cell. Secondly Ca 2+ indirectly activates proteins, called myofilaments, resulting in muscle contraction. The two main myofilaments in cardiac (and skeletal) muscle are actin and myosin.
In humans, the DMD gene is located on the short (p) arm of the X chromosome between positions 21.2 and 21.1. Dystrophin is a rod-shaped cytoplasmic protein, and a vital part of a protein complex that connects the cytoskeleton of a muscle fiber to the surrounding extracellular matrix through the cell membrane.