Neurotransmitters Flashcards
A patient presents with motor deficits. Based on their history, you suspect they have Parkinson’s disease. What dopamine neurons have likely been lost in this patient?
Substantia nigra dopamine neurons
Norepinephrine, epinephrine, dopamine, serotonin, and histamine are all examples of what class of neurotransmitter?
Biogenic amines / monoamines
What neurotransmitter receptor plays a role in synaptic plasticity and memory?
NMDA receptors
This purine receptor plays a role in mechanosensation and pain.
P2X - ionotrophic
What is the function of GABA as a neurotransmitter?
Inhibitory in the brain
What is the function of the nigrostriatal dopamine pathway?
Motor
What enzyme converts glutamine to glutamate in the pre-synaptic neuron?
Glutaminase
What type of Ach receptors are most common in the brain?
Muscarinic
Endocannabinoids can bind the pre-synaptic neuron via retrograde signaling. What is this effect?
They can affect the release of neurotransmitter from the pre-synaptic neuron.
How are catecholamines mostly cleared from the synaptic cleft?
Reuptake into the pre-synaptic neuron. Remainder is broken down by the liver.
What enzyme is responsible for converting norepinephrine to epinephrine?
PNMT
CNS neurotransmitters, such as Ach and NE, are located where?
Locus coeruleus
What neurotrophin is responsible for decreasing axonal growth and dendritic complexity?
p75
What dopamine pathway controls prolactin release?
Tuboinfundibular
Catecholamines are generated from what molecule?
Tyrosine
This dopamine pathway plays a role in reward & pleasure.
Mesolimbic
True/False. Myasthenia gravis is caused by decreased Ach release.
False. Ach release is normal, however immune cells target and destroy Ach receptors. As such, less receptors are available for Ach binding.
What is an example of a metabotropic purine receptor and its function?
A2A - increases GABA release to facilitate arousal
What receptors are targetted by muscle relaxants?
GABA(B)
These receptors activate G-coupled receptors and have longer-lasting effects.
Metabotrophic
How does an AMDA receptor differ from an NMDA receptor?
An AMDA receptor only allows entry of Na+. The NMDA receptor allows entry of Na+ & Ca+, but is blocked by Mg+. Two action potentials are required to displace the Mg+ and open the channel.
Describe the effects of low and high serotonin levels.
Low serotonin - depression, suicidal ideation, violence
High serotonin - mania, aggressive behavior
What is the first brain structure damaged during Alzheimer’s disease?
Basal forebrain - motor problems likely present before memory loss and behavior change
Where is serotonin produced?
Raphe nuclei
All dopamine receptors are metabotropic. Which receptors are inhibitory?
D2, D3, D4
Orexins play a role in the sleep/wake cycle. Where are they released from?
Lateral hypothalamus
What is the primary inhibitory neurotransmitter for the spinal cord?
Glycine
What molecule is used to derive serotonin?
Tryptophan
What is the effect of ATP on glutamate release from the pre-synaptic neuron?
ATP inhibits glutamate release. Dopamine can stimulate an astrocyte to release ATP.
What common neurotransmitters are catecholamines?
Epinephrine, norepinephrine, dopamine
All dopamine receptors are metabotropic. Which receptors are stimulatory?
D1 & D5
Serotonin is reuptook via serotonin transporters. How does MDMA affect reuptake?
MDMA causes release of all serotonin into the synaptic cleft
What histamine receptors are located in the brain to play a role in homeostasis, memory, and sleep/wake cycle?
H1, H2, & H3. H4 is located throughout the body and functions in immune response
What types of receptors open ligand-gated ion channels?
Ionotrophic
What dopamine pathway plays a role in behavior, cognition, and mood?
Mesocortical
What is the primary excitatory neurotransmitter for the CNS?
Glutamate
