Described the actions of the esters and ethers of choline on isolated organs and their relationship to muscarinic, pharmacologist, physiologists, chemists, and biochemists have applied their knowledge to understand the actions of the cholinergic nerve and its neurotransmitter Dale Found in the Central and Peripheral nervous system and use Ach as their neurotransmitter Cholinergic Receptor Cholinergic receptors use ____ as neurotransmitter Ach 2 kinds of cholinergic receptor Nicotinic Muscarinic Ionotropic receptors or Ligand-gated ion channels Responsive to Ach and Nicotine Nicotinic Metabolic receptors or G-protein couple receptors Responsive to Ach and Muscarine Muscarinic 2 subtype of Ncotinic Cholinergic Receptors Ganglionic receptor (neural) N2 Muscle receptor (somatic) N1 Ganglionic receptor (neural) N2 is blocked by ______ and ________ but stimulated by __________ and ___________ hexamethonium trimethaphan tetramethylammonium dimethyl 4-phenylpiperazinium Muscle receptor (somatic) N1 is blocked by ______, _______ and ________ and stimulated by ________ succinycholine d-tubocurarine decamethonium phenyltrimethylammonium Muscle receptor (somatic) N1 is blocked by ______, _______ and ________ and stimulated by ________ succinycholine d-tubocurarine decamethonium phenyltrimethylammonium Post synaptic on neuromuscular junctions Muscle receptor (somatic) N1 Found  in both the CNS and PNS Ganglionic receptor (neural) N2 responsible for transmission at sympathetic and parasympathetic ganglia Ganglionic receptor (neural) N2 responsible for skeletal muscle contraction Muscle receptor (somatic) N1 Second-messenge systems that cause muscle contraction Phosphoinositol system Second-messenge systems that cause smooth muscle relaxation Adenylate cyclase Second-messenge systems that slows heart rate Ion channels provide the primary source of acetylcholine to the cerebral cortex, and are known for their role in promoting cortical activation during both wakefulness and during rapid eye movement (REM) sleep Cholinergic Neurons the specific study of neurochemicals  including neurotransmitters and other molecules (such as psychopharmaceuticals) that influence the function of neurons Neurochemistry is the study of the chemistry involved in the relative spatial arrangement of atoms and molecules Stereochemistry study of spatial arrange of cholinergic atoms and molecules Cholinergic Stereochemistry is a method of determining the arrangement of atoms within a crystal, in which a beam of X-rays strikes a crystal and diffracts into many specific directions X-ray crystallography a physical phenomenon in which nuclei in a magnetic field absorb and re-emit electromagnetic radiation Nuclear magnetic resonance encompasses all theoretical methods and computational techniques used to model or mimic the behaviour of molecules. Molecular modeling by computation The study of the relationship between a drug's molecular structure and the drug's biological activity Structure Activity Relationship Receptors that block synapses of the parasympathetic nerves Cholinergic Receptor Antagonists other name of cholinergic antagonist cholinergic blockers, parasympatholytics or anticholinergic inhibit the cholinesterase enzyme from breaking down ACh, increasing both the level and duration of the neurotransmitter action AChE inhibitors or anti-cholinesterases is an enzyme that specifically cleaves Ach to acetate and choline and, thus, terminates its actions Acetylcholinesterase 2 types of cholinesterases in humans Butyrylcholinesterase (BuChE) Acetylcholinesterase (AChE) 2 groups of AChEi Reversible Inhibitors Irreversible Inhibitors Agents that block the transmission of ACh at the motor end plate NEUROMUSCULAR BLOCKING AGENTS depolarize the membrane of the muscle end plate. Depolarizing Blocking Agents was a term used to describe collectively the very potent arrow poisons used since early times by the South American Indians curare