Mammalian sympathetic ganglion cells, typically obtained from laboratory rats and guinea pigs, are often used as models by physiologists to explain the biochemistry of nerve excitation and the effects that chemical substances, such as nicotine, may have on these processes. Such cells are also employed in medical research studies exploring possible solutions to devastating neuromuscular diseases such as cerebral palsy and muscular dystrophy, and potential therapies, where human experimentation is considered unethical and often illegal.

The sympathetic nervous system, the fight or flight system, allows a mammal to react rapidly by increasing blood pressure and heart beat rate, and by retarding the digestive process. Originating in the spinal cord, sympathetic nerves project to a chain of ganglia (nerve concentrations) located near the spinal cord. Usually, a synapse is made in the ganglion with another neuron, the post-ganglionic neuron, and it targets either a muscle or a gland. Mammalian sympathetic ganglia use acetylcholine as a neurotransmitter while the synapses of the target organs, and the post-ganglionic neurons, use norepinephrine.

As part of the autonomic nervous system, the sympathetic nervous system works in concert with the parasympathetic nervous system, the portion responsible for rest and digestive responses. In 1936, Sir Henry Hallett Dale received the Nobel Prize in physiology and medicine for his pioneering work describing the chemical transmission of nerve impulses, as studied with acetylcholine in the mammalian sympathetic ganglia. Playing a critical role in biological optics, ganglion cells are the final output neurons of the vertebrate retina, in which the axons of the ganglia make up the optic nerve.

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