How can nicotine cause both sympathetic and post-sympathetic effects? I.e. why does in increase heart rate but also cause diarrhea?
I get why it would cause hypertension; most vessels don't have parasympathetic innervation, therefore there's nothing to counterbalance the stimulus of nicotine binding to the post-ganglionic nicotinic receptor.
GI has both para and sympathetic innervation. Heart has both sympathetic and parasympathetic innervation. We know nicotine binds to the postganglionic NT transmitter and should stimulate both para and symp. Why then do these systems dominate?
I get why it would cause hypertension; most vessels don't have parasympathetic innervation, therefore there's nothing to counterbalance the stimulus of nicotine binding to the post-ganglionic nicotinic receptor.
GI has both para and sympathetic innervation. Heart has both sympathetic and parasympathetic innervation. We know nicotine binds to the postganglionic NT transmitter and should stimulate both para and symp. Why then do these systems dominate?
