They are released in response to an action potential, which sends a biological-electrical shock down the axon. At the end of the axon, the neurotransmitters are released, and they travel across the synaptic gap. They hit the receptor on a dendrite of another neuron, and attach to receptor sites. The receptor sites can identify different types of neurotransmitters. Once it identifies the neurotransmitter, it passes the message on to the next neuron through the same process.
Here are some of the most basic, prominent neurotransmitters.
Acetycholine-- ACH= learning, memory, muscle action
- alzheimer's disease: hippocampus (which is responsible for memories) dies off
- black widow spider bite: venom releases all of you acetycholine at once, you cramp up all over
- botulism, curane darts: stop acetycholine from being transmitted-- causes paralysis
Seratonin= mood, slee, arousal, hunger
- food coma, staying up late and getting delerious+giggly, milk before bed, ecstasy
- ecstasy lowers seratonin levels permanently-- causes depression
- anti-depressants bring seratonin levels up slowly, in a controlled way
Dopamine= movement, learning, attention, emotion
- schizophrenia, parkinson's, drugs that give you a sense of euphoria
Norepinephrine= alertness and arousal
GABA= inhibitory neurotransmitter
glutamate= excitatory, involved in memory, often overstimulating (in MSG)
Lock & Key mechanism: neurotransmitters bind to receptors of receiving neuron in a lock+key shape
- agonist= synthetic molecule that mimics neurotransmitter: fits closely enough to receptor site to activate a response to another similarly-shaped, naturally occurring neurotransmitter
- example: morphine imitates endorphins because its molecule is similarly shaped
- antagonist= fits into receptor site but does not activate the receiver, simply blocks the path
- curare poison blocks the receptor designated for ACh, so ACh can't get through and you become paralyzed
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