-
Types of neurotransmitters
- acetylcholine
- biogenic amines (catecholamines, serotonin)
- peptides
- amino acids
-
Neurotransmitter Actions
- Excitatory NT - increase Na permeability; depolarizeInhibitory NT - increase Ca & K permeability; hyperpolarize
-
Types of NT receptors
- G protein linked receptors: hormone like receptors; cascades (2nd messenger)
- ex: Adrenergic, dopamine, muscarinic cholinergic, opiate
- Ligand gated ion channel: fast effects; closed at rest, opens w/NT; excitatory or inhibitory
- ex: nicotinic cholinergic, GABA, NMDA
-
Acetylcholine Synthesis
Acetyl coA + Choline --(choline-acetyl transferase)>>Acetylcholine + CoA-SH
-
Nicotinic Acetycholine Receptor
- neuromuscular junction
- ligand gated ion channel
-
Action of Acetyl Cholinesterase
- Ach --(Achesterase)>> Acetyl Enzyme Intermediate + Choline
- Acetyl Enzyme Intermediate --(H2O) >> Ach-esterase + H+ + acetate
-
Cholinergic Synapses & inhibitors
Nicotinic Receptors
Muscarinic Receptors
- Nicotinic:
- ligand gated Na
- NM junction, autonomic ganglia & brain
- X - curare
- Muscarinic:G-protein
- parasympathetic tissues
- sweat glands
- brain
- X- atropine & scopolamine
|
|
