Nerve agents stop the body from breaking down the acetylcholine neurotransmitter, overwhelming the nervous system and causing convulsions that can lead to death within minutes of exposure.

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Acting as a messenger between the central nervous system and the major organs, the vagus nerve slows the heart rate (through the release of the neurotransmitter acetylcholine), calms the immune response (by controlling the release of proteins called cytokines), and communicates with the muscles that control respiration and digestion.

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