_______________________a investigations of the sarcolemma penetrating deep into the interior of the muscle cells
• Each skeletal muscle cell is individually stimulated by a motor neuron. • The neuromuscular junction is the place where the terminal portion of a motor neuron axon meets a muscle cell membrane, separated by a synaptic cleft. • An action potential arriving at the axon terminal brings about the release of acetylcholine, which leads to depolarization of the motor end plate. Page 5. Overview of Neuromuscular Junction Activity. • The muscle cell, including the T Tubules are polarized. Stimulation of the motor end plate on a muscle cell by acetylcholine triggers depolarization resulting in contraction of the sarcomeres. Hundreds or thousands of muscle fibers (cells) bundle together to make up an individual skeletal muscle. Muscle cells are long, cylindrical structures that are bound by a plasma membrane (the sarcolemma) and an overlying basal lamina and when grouped into bundles (fascicles) they make up muscle. A T-tubule is a deep invagination of the sarcolemma, which is the plasma membrane, only found in skeletal and cardiac muscle cells. These invaginations allow depolarization of the membrane to quickly penetrate to the interior of the cell. ... a role in remodelling of sarcolemma, sarcoplasmic reticulum, and myofibrils. Some muscles (skeletal muscles) will not contract unless stimulated by neurons; other muscles (smooth & cardiac) will contract without nervous stimulation but their contraction can be influenced by the nervous system. Thus, the nervous and muscle systems are closely interconnected. Invaginations of the sarcolemma penetrating deep into the interior of the muscle cell. ... Full article >>>. ... faintly detectable in a patchy distribution along the sarcolemma in our patients. ... disturbance of sarcolemma-extracellular matrix interaction leading to ... Page 1. Introduction. • Motor neurons stimulate muscle cells to contract at the neuromuscular junction. Page 2. Goals. • To examine the structure of a neuromuscular junction. • To understand the sequence of events occurring at the neuromuscular junction following a stimulus. Page 3. The cell membrane of a muscle cell is called the sarcolemma, and this membrane, like that of neurons, maintains a membrane potential. So, impulses travel along muscle cell membranes just as they do along nerve cell membranes. However, the 'function' of impulses in muscle cells is to bring about contraction. A T-tubule is a deep invagination of the sarcolemma, which is the plasma membrane, only found in skeletal and cardiac muscle cells. These invaginations allow depolarization of the membrane to quickly penetrate to the interior of the cell. Full article >>>. ... 1 - Because skeletal muscle is voluntary muscle, contraction requires a nervous impulse. So, step 1 in contraction is when the impulse is transferred from a neuron to the SARCOLEMMA of a muscle cell. 2 - The impulse travels along the SARCOLEMMA and down the T-TUBULES.
T-tubule