(11) Quit Smoking
What are the physiological effects of nicotine?
Now that we have a general outline of the neuroanatomy of acetylcholine, and about where nicotine receptors are and the general impact they have on the body, we are more informed about nicotine’s physiological effects. Obviously, this is very complicated, as there are many receptor subtypes. Different locations in the body utilize different subtypes.
First, let’s focus on the sympathetic nervous system locations:
Those include (1) the adrenal medulla, considered essentially to be its own sympathetic ganglion, which releases the hormone adrenalin (along with other hormones); (2) the neuromuscular junction, which causes the skeletal muscles to activate; and finally, (3) the sweat glands on the skin.
Thus, nicotine plays a role in releasing adrenalin, activating skeletal muscle, and keeping the body temperature regulated when it exerts itself.
While skeletal muscles respond to nicotine, its direct impact is relatively insignificant at the doses normally ingested in the form of cigarette smoke. However, muscle twitching can occur in an overdose.
Nicotine’s impact on muscles is not why it is used nor is it related to its addictive potential. Here we can see how nicotine is associated with energy and action.
Nicotine also plays a role in the parasympathetic nervous system, principally through its actions on the autonomic ganglion, which stimulates the parasympathetic nervous system and, as a result, its terminal actions on various organ systems involved in rest and restoration.
These effects include activation of the gut, slowing of the heart, relaxation of the blood vessels, and stimulation of the sex organs.
Acetylcholine is responsible for arousal and erection via the parasympathetic nervous system, while epinephrine is responsible for orgasm and ejaculation via the sympathetic nervous system, both of which respond to nicotine. In early history, nicotine was thought to be an aphrodisiac, and this explains why.