Autonomic Pharmacology I (Cholinergic (Parasympathetic) Mechanisms)

At the end of the course, students should be able to: 1. identify the main steps involved in neurotransmission; 2. recognise the anatomical and chemical characteristics of the parasympathetic and sympathetic nervous system; 3. identify major pre- and post- synaptic mechanisms by which drugs act.; 4. describe the metabolic fate of cholinergic neurotransmitter; 5. recognise the major differences between direct and indirect acting cholinergic agonists; 6. explain the structural and functional differences between muscarinic and nicotinic receptor 7. types and subtypes, their locations in the body and mechanisms of action; 8. discuss the pharmacological actions, uses, side effects and structure activity relationship of drugs acting directly and indirectly on the parasympathetic nerve ending; and 9. explain the pharmacology of drugs acting on the autonomic ganglia and Neuromuscular Junction.

Introduction - Theory of Chemical Neurotransmission Evidence for Acetylcholine as a Cholinergic neurotransmitter. Detection and Bioassay of acetylcholine. Cholinergic receptors, sites of action of acetylcholine at the Neuromuscular junction. Agonists and antagonists of cholinergic transmission. Parasympathomimetic and parasympatholytic drugs. Structure – Activity Relationships among the cholinergic and anticholinergic agents. Cholinesterases and anti- cholinesterases. Properties and uses of anti-cholinesterases (reversible and irreversible). Brief mention of cholinesterase reactivators (pralidoxime, obidoxime) and their uses. Neuromuscular transmission and drugs which enhance neuromuscular transmission. Neuromuscular Blockade. Smooth muscle relaxants. Ganglion stimulation and blockade and their properties.