Neurotransmitters of the Autonomic Nervous System

(From Watcha MR, White PF. Postoperative nausea and vomiting. Its etiology, treatment, and prevention. Anesthesiology. 1992;77:162-184, with permission.)

Preganglionic fibers pass through the white ramus to a paravertebral ganglia, where they may synapse, course up the sympathetic chain to synapse at another level, or exit the chain without synapsing to pass to an outlying collateral ganglion.