Skeletal muscle innervation Path of action neuron Neuromuscular Axon junction e Motor end plate Supporting cell Synaptic terminal Sarcolemma Mitochondrion Myofibril Muscle b
6 Skeletal Muscle Innervation
Illustration of the neuromuscular Junction(NMJ Motor neuron fiber Nerve fiber branches Muscle fiber nucleus Motor end plate Myofibril of muscle fiber m e Mitochondria Synaptic vesicles Synaptic cleft Folded sarcolemma Motor end plate
7 Illustration of the Neuromuscular Junction (NMJ)
New lon Channel Players Voltage-gated ca2+ channel >in presynaptic nerve terminal >mediates neurotransmitter release P Nicotinic Acetylcholine receptor channel >in muscle neuromuscular junction (postsynaptic membrane or end plate) >mediates electrical transmission from nerve to muscle Nerve fiber branches Muscle fiber nucleus Motor end plate Myofibril of muscle fiber Motor end plate
8 New Ion Channel Players ➢Voltage-gated Ca2+ channel ➢in presynaptic nerve terminal ➢mediates neurotransmitter release ➢Nicotinic Acetylcholine Receptor Channel ➢in muscle neuromuscular junction (postsynaptic membrane, or end plate) ➢mediates electrical transmission from nerve to muscle
Neuromuscular transmission Axon Axon terminal Skeletal Muscle
9 Neuromuscular Transmission Skeletal Muscle Axon Axon Terminal
Depolarization Neuromuscular Nerve出i Transmission opens ca nnels potential invades Step by step axon terminal Look here
10 Neuromuscular Transmission: Step by Step Nerve action potential invades axon terminal - + - - - - - - + + + + + + + - - - + + Depolarization of terminal opens Ca channels Look here + +