Transcript Drugs and Synapse - Central Connecticut State University

Neural Communication
The Nerve Impulse
Neural Communication
Otto Loewi
• Nobel Prize in 1936
• Forced to leave
Germany in 1938
• Became US citizen in
1941
• Worked at Woods
Hole Institute
• Name pronounced as
“low”
Loewi’s Experiment
KW 5-2
The first known neurotransmitter
• acetylcholine
• first neurotransmitter identified
(by Otto Loewi, 1921)
• Movement: causes muscles to
contract
• Memory: dies in Alzheimer’s
disease
Autonomic NT’s
KW 5-17
Ach Pathways
KW 5-19
Synapse structures
KW 5-4
Steps
KW 5-5
Step 1
ACh Synthesis
Acetylcholine
Bonded to form
Step 2
Step 3
Step 4
Step 5
Step 6
Modifying Neural Messages
• drug agonists - enhance potency of
neurotransmitter
• drug antagonists - reduce effectiveness
Agonist and Antagonists
Neurotransmitter
molecule
Receptor site on
receiving neuron
Receiving cell
membrane
Agonist mimics
neurotransmitter
Antagonist
blocks
neurotransmitter
Pain Killers
• Endorphins
•
natural opiates
•
natural key
• Morphine
•
Opium poppy
•
Agonist
• Naloxone
•
Antagonist
Agonist and antagonist
Step 7
Reuptake and
breakdown
AChE
Ach and
AChE
KW 5-11
NT characteristics
KW 5-9
Monoamine Neurotransmitters
• the catecholamines:
– Dopamine
• found at substantia nigra and limbic
system
• regulates emotion & movement
– Norepinephrine
• found in brain stem and subcortex
• regulates emotion, reward, sleep, mood
– Epinephrine
• Found adrenal glands
• may help regulate blood pressure
Catecholamine
synthesis
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Catecholamine Pathways
KW 5-19
Neural Communication
Dopamine pathways
Monoamine Neurotransmitters
• Serotonin
– found in raphe nuclei in
brain stem
– regulates temperature,
sensory perception and sleep
onset
– LSD and antidepressants
affect serotonin
(antidepressants particularly
affect serotonin reuptake)
Serotonin
Serotonin Pathways
KW 5-19
Neural Communication
Serotonin pathways
Drug Effects
Classes of NT