What effect does nicotine have on the parasympathetic and sympathetic nervous...

[lll]

...systems? And what are the consequences? (i.e. which common side-effects of smoking can be attributed to activation of autonomic neurons) Explain why.

Thanks in advance!

[Eli]

By binding to nicotinic acetylcholine receptors, nicotine increases the levels of several neurotransmitters - acting as a sort of "volume control". It is thought that increased levels of dopamine in the reward circuits of the brain are responsible for the euphoria and relaxation and eventual addiction caused by nicotine consumption. Nicotine has a higher affinity for acetylcholine receptors in the brain than those in skeletal muscle, though at toxic doses it can induce contractions and respiratory paralysis.Nicotine's selectivity is thought to be due to a particular amino acid difference on these receptor subtypes.