Alpha motor neuron

The Alpha Motor Neuron (also known as α-Motor Neuron or Lower Motor Neuron) is a type of motor neuron that innervates skeletal muscle fibers. These neurons are responsible for the direct control of muscles in the body, including both voluntary and involuntary movements.

Structure

Alpha motor neurons are large, multipolar neurons located in the anterior horn of the spinal cord. They have a cell body, a single axon, and multiple dendrites. The axon of an alpha motor neuron exits the spinal cord through the ventral root and travels to the muscle it innervates.

Function

The primary function of alpha motor neurons is to trigger muscle contractions. They do this by releasing the neurotransmitter acetylcholine at the neuromuscular junction, which then binds to receptors on the muscle fiber, causing it to contract.

Clinical Significance

Damage to alpha motor neurons can result in a variety of motor disorders, including Amyotrophic lateral sclerosis (ALS), Spinal muscular atrophy (SMA), and Polio.

See Also

• Motor neuron
• Neuromuscular junction
• Motor unit
• Muscle contraction