Autonomic nervous system - sympathetic nervous system (English)

The origin of the sympathetic nervous system is found within the thoracic and lumbar segments of the spinal cord, which is why it is also called the thoracolumbar division. The sympathetic pathway can be simplified into the following components: preganglionic neurons, sympathetic ganglia, and postganglionic neurons. The preganglionic (presynaptic) neurons are located inside the thoracic and lumbar segments (T1-L2) of the spinal cord. They project axons (preganglionic fibers) that synapse with the postganglionic (presynaptic) neurons inside the sympathetic ganglia, which are typically found near the vertebral column. The postganglionic neurons give off long axons (postganglionic fibers) that leave the ganglia and project onto visceral effectors, where they release the neurotransmitter norepinephrine.