Introduction to Autonomic Pharmacology
Start with the big picture
The autonomic nervous system includes sympathetic, parasympathetic, and enteric divisions. Both sympathetic and parasympathetic preganglionic fibers release acetylcholine at nicotinic receptors, while postganglionic signaling differs across pathways, with several important sympathetic exceptions. The topic traces catecholamine synthesis and removal, acetylcholine breakdown, and the G-protein pathways linked to major receptor families. It also introduces autoreceptor and heteroreceptor modulation, drugs that alter uptake, storage, or transmitter breakdown, and the distinction between direct receptor agonists and antagonists and indirect agents. Finally, it explains how baroreceptor reflexes and dominant resting tone can shape responses to autonomic drugs, and how chronic receptor exposure may change sensitivity.
What you'll learn
- Identify the three divisions of the autonomic nervous system and their basic organization.
- Describe major autonomic neurotransmitters, receptors, and sympathetic exceptions.
- Outline catecholamine synthesis and the removal of norepinephrine and acetylcholine.
- Relate receptor families to G-protein coupling and second-messenger pathways.
- Explain how modulation, reflexes, resting tone, and receptor regulation affect drug responses.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
