Sweat glands: Innervation

The sweat glands are innervated by the sympathetic nervous system and are part of the fight or flight response system. Their innervation consists of two parts, a preganglionic and postganglionic neuron. The preganglionic neuron is short, originates from the thoracolumbar region of the spinal cord, uses acetylcholine as its neurotransmitter, and synapses with the postganglionic neuron via a nicotinic acetylcholine. The postganglionic neuron for sweat gland innervation differs from other sympathetic postganglionic neurons in that it releases acetylcholine to act on muscarinic receptors; all other sympathetic postganglionic neurons, with the exception of the adrenal medulla, use norepinephrine.