Neurotransmitters: Catecholamines

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NeurotransmittersCatecholamines
AcetylcholineChapters 5 6

• Catecholamines
• Dopamine
• Norepinephrine
• Epinephrine
• Acetylcholine
• Serotonin
• Glutamate
• GABA

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Neurotransmitter Families
Neurotransmitters
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Structural features of catecholamines
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Synthesis of Catecholamines
rate-limiting enzyme
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CatecholeminesSome adjectives

• Dopamine (DA)
• dopaminergic
• Norepinephrine (NE)
• noradrenergic
• Epinephrine (EPI)
• adrenergic

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Storage of Catecholaminesvesicular monoamine
transporter protein (VMAT2)
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Behavioral effects of reserpine
http//home.caregroup.org/clinical/altmed/interact
ions/Images/Herbs/rauwolfi.gif
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Dopamine Systems in the Brain

• Mesolimbic pathway
• Reinforcement
• Mesocortical pathway
• Planning
• Nigrostriatal pathway
• Movement

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Symptoms of Parkinsons Disease

• Difficulty moving
• Tremor in resting body parts
• Loss of balance, frequent falls
• Cognitive dysfunctions in memory, abstract
  thinking, language
• Premature death

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Damage to the substantia nigra
http//www.urmc.rochester.edu/neuroslides/slides/s
lide199.jpg
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Causes of Parkinsons Disease

• Degeneration of substantia nigra
• Less dopaminergic activity in basal ganglia
• Discovery of MPPP ? MPTP and MPP

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A typical dopaminergic neuron
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D1 and D2 receptors
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Catalepsy can be produced by D2 receptor
antagonists
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Norepinephrine
http//homepage.psy.utexas.edu/homepage/class/Psy3
01/Salinas/sec2/Brain/31.GIF
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Role of the locus coeruleus in vigilance
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Synthesis of acetylcholine (ACh)
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Functions of Acetylcholine (ACh)

• Neuromuscular junction (movement)
• Central nervous system (learning and memory)

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cholinergic synapse
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Acetylcholine Receptors

• Nicotinic receptors
• Neuromuscular junctions
• Ionotropic (ion channel)
• Curare works on these receptors
• Muscarinic receptors
• Metatropic (second messengers)
• Hippocampus, striatum
• Morphine
• Also located in heart and smooth muscles
• Nightshade

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Cholinergic synapses in the parasympathetic and
sympathetic branches of the ANS