Paramedic National Registry Practice Exam 2025 – The All-in-One Guide to Master Your Certification!

The neurotransmitter primarily associated with the sympathetic nervous system is norepinephrine. This neurotransmitter plays a crucial role in the body's "fight or flight" response, which is characteristic of sympathetic activation. When the sympathetic nervous system is stimulated, norepinephrine is released from the postganglionic neurons, causing an increase in heart rate, dilation of airways, and other physiological changes that prepare the body to respond to stress or danger.

While other neurotransmitters like acetylcholine are involved in the autonomic nervous system, they primarily function in the parasympathetic division, which is responsible for "rest and digest" activities. Serotonin and dopamine have important roles in mood regulation and reward pathways in the brain but are not the primary neurotransmitters that signal sympathetic activation. Thus, norepinephrine stands out as the key neurotransmitter that mediates the effects of the sympathetic nervous system.