Motor nerve fiber (None commonly used)

A motor nerve fiber, also known as an efferent nerve fiber or motor axon, is the long projection from a motor neuron that transmits electrical impulses away from the neuron's cell body toward skeletal muscle fibers or glands. These fibers are typically myelinated in vertebrates—myelin sheaths increase conduction speed—and form part of larger bundles called nerves in the peripheral nervous system. At their terminals, they form synapses known as neuromuscular junctions with muscle cells; here they release neurotransmitters such as acetylcholine that trigger muscle contraction[1][3]. Motor nerve fibers can be classified by diameter and conduction velocity into alpha (Aα), beta (Aβ), and gamma (Aγ) types—the largest being responsible for rapid activation of skeletal muscles[4][6]. Dysfunction or degeneration leads to various neurological diseases affecting movement control.

Other names

Efferent nerve fiberEfferent axonMotor axon

Not applicable for direct targeting. For agents affecting these fibers: Blockade of action potential propagation by inhibiting sodium channels; Inhibition of acetylcholine release at neuromuscular junctions.