Week 1 Friday Lecture - Prof. Gandhi, Leon, and Nicholas PDF

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Prof. Gandhi, Leon, and Nicholas ...

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Week 1, Friday Lecture Ligand-gated Sodium channels open (2) before voltage gated channels (3) in action potential graph Then at point 4 of the graph, voltage-gated potassium channels open up The Sodium-Potassium pump resets at point 5. Action potential happens in the axon End of action potential at the synapse  neurotransmitters transfer to post-synaptic surface Happy Accidents Sensory info = peripheral nervous system (your nerves and ganglion) Emil DuBois Reymond 1877 – first to record electrical activity during a voluntary muscle contraction George Oliver and Edward Schafer – tested adrenal gland extracts on blood pressure Adrenaline is also known as norepinephrine. Adrenaline stimulates flight-or-fight. Walter Dixon (1907)—discovered the Amanita Muscaria mushroom (flying reindeer hallucinations) Amanita Musacaria mimics a compound called Muscarine. Muscarine stimulates your resting, digestive instincts. The heart slows down. Sir Henry Dale—helped discover Acetylcholine from the Ergot fungus Otto Loewi—Discovers vagal substance and accelerating substance. He stimulated the vagus nerve of a frog and the heart of the frog slowed down. The heart slowed down with both electrical stimulation and chemical stimulation. Discovered first known neurotransmitter. Vagusstoff=acetylcholine=muscarine Acceleransstof=adrenaline=norepinephrine (epinephrine) Happy accident: Iproniazid and Isoniazid (1952) Tuberculosis is a bacterial infection. Iproniazid and Isoniazid were developed to treat TB. The drugs didn’t cure TB but were Monoamine Oxidase (MAO) Inhibitors. MAO breaks down the NTs: Serotonin (Makes you happy), Dopamine, and Norepinephrine. Two ways to stop NT signal: Recycle the NT that has been released (re-uptake transporters). 2. Break down the NT by enzymes like MAO. MAO takes serotonin out of the synapse and when MAO is inhibited, Serotonin floods the synapse and people feel really really happy. MAO inhibition results in increased availability of neurotransmitter in the synapse. Ecstasy is a drug that releases a lot more serotonin than norepinephrine and dopamine, so people feel happy and warm.

MAO’s put you in flight-or-fight mode. They make your peripheral nervous system alert and your heart beats a lot faster. Bernard Katz won nobel in 1970 and he measured action potentials. Demonstrated quantal release of acetylcholine. Vesicles hold a certain amount of NTs Ricardo Miledi (UCI guy)—Calcium is needed to help NT’s be released to post-synaptic neuron....