Question

Identify the pre- and postganglionic neurotransmitters of the Sympathetic and Parasympathetic nervous system.

Answer 1

Answer:

For the sympathetic nervous system:

i. the preganglionic neurotransmitter is acetylcholine, while

ii. the postganglionic neurotransmitter is norepinephrine

For the parasympathetic nervous system both pre- and postganglionic neurones use acetylcholine as their neurotransmitter.

Explanation:

Sympathetic and parasympathetic nervous system are the two components of the autonomic nervous system.

The sympathetic system arises from the the thoracolumbar (T1-L2) region of the spinal cord.

The parasympathetic nervous system originate from

i. the cranial nuclei in the brainstem (brainstem nuclei cranial nerve III, VII, IX, and X), and

ii. sacral nerves (S2-S4).

Preganglionic and postganglionic neurones link both sympathetic and parasympathetic systems to their effector organs.

At synaptic junctions in the autonomic ganglia ththe preganglionic neuron of both sympathetic and parasympathetic nervous system use cholinergic neurotransmitter (acetylcholine). The postganglionic neurotransmitters are not the same for both sympathetic and parasympathetic systems. The sympathetic uses norepinephrine (adrenergic) while the parasympathetic maintains the acetylcholine.