Acetylcholine and norepinephrine both affect smooth muscle contraction. They stimulate contraction in some muscles and inhibits contraction in others.
norepinephrine. Acetylcholine mainly causes smooth muscle contraction, while norepinephrine can either cause contraction or relaxation depending on the type of receptor it binds to on the smooth muscle cell.
Smooth Muscle Cells
Breaking down acetylcholine can lead to muscle relaxation because acetylcholine is a neurotransmitter that stimulates muscle contraction. When acetylcholine is broken down, the signal for muscle contraction is reduced, resulting in muscle relaxation.
acetylcholine (ACh)
Sarcolema receptors
Occurs when acetylcholine (ACh) accumulates in the neuromuscular junction. It is called a tetanic contraction.
Acetylcholine is the primary neurotransmitter responsible for muscle movement. It is released from motor neurons at the neuromuscular junction to stimulate muscle contraction.
Acetylcholine is the primary neurotransmitter released by motor neurons at the neuromuscular junction to stimulate muscle contraction. It binds to receptors on the muscle cell membrane, initiating a series of events that ultimately lead to muscle contraction.
ACh (acetylcholine) binds to receptors at the NMJ (neuromuscular junction) to induce contraction of muscle.
Acetylcholine is the chemical that transmits signals across the neuromuscular junction. It binds to receptors on the muscle cell membrane, leading to muscle contraction.
specific cardiac and smooth muscle fibers
"A muscle cell remains contracted until the release of acetylcholine stops and an enzyme produced at the axon terminal destroys any remaining acetylcholine."