Neurotransmitters Flashcards
Glutamate (where is it synthesized & found)
- created in most neurons and glial cells
- found throughout CNS:
- cortex, SC, Brainstem, Hippocampus, Cerebellum
- motor, sensory and cognitive neurons
Glutamate (post-synaptic response & function)
-Excitatory
function:
- Involved in virtually every major excitatory brain function
- Learning and memory
- Synaptic Plasticity (=the brain’s ability to change!)
Glutamate (Receptors)
-Ionotropic: AMPA receptors, NMDA receptors, Kainate receptors
-Metabotropic: (G-coupled protein receptors) – MANY
different specifically named receptors
-Modulate glutamate release
-Affect postsynaptic excitability
Acetylcholine (where is it synthesized & found)
Widely distributed – Synthesized in presynaptic terminals of spinal cord anterior horns, basal ganglia, autonomic nervous system, thalamus, cerebellum, and brainstem (pons & medulla).
Acetylcholine (post-synaptic response & function)
- Excitatory (neuromuscular junctions, autonomic ganglion and gland)
- Inhibitory (Smooth muscle and cardiac muscle)
Functions:
- Plays an important role at neuromuscular junctions to elicit muscle contraction
- Also plays role in autonomic function and neuromodulation
- In CNS, involved in wakefulness, attentiveness, anger, sexuality, amongst other things
ACh (receptors)
- Ionotropic: nicotinic receptors (excitatory)
- Metabotropic: muscarinic receptors (excitatory or inhibitory)
Glutamate (Agonist/Antagonists)
- Phencyclidine (aka PCP, “angel dust”)
- Riluzole (primary medication used with ALS)
ACh (Agonist/Antagonists)
Agonists & Antagonists
GABA (where is it synthesized & found)
- Most abundant NT inhibitor in CNS – widely distributed.
- Synthesized in the cytoplasm of the presynaptic neuron from the precursor glutamate
- Increased accumulation found in cell bodies located in basal forebrain, thalamic reticular nucleus, hypothalamic ventrolateral preoptic area
GABA (post-synaptic response & function)
inhibitory
function:
-Motor control, vision, alertness, anxiety
-Inhibits motor, sensory, and cognitive neurons
–> sedation, muscular/cardiorespiratory
relaxation, pain inhibition
GABA (receptors &agonist/antagonist)
Receptors:
- Ionotropic
- Metabotropic
Agonists & Antagonist
Glycine (where is it synthesized & found)
- Synthesized from serine
- Found in proteins; one of the 20 most common amino acids
- Mainly found in brainstem and spinal cord
Glycine (post-synaptic response & function)
inhibitory
Function:
- Inhibits spinal interneurons
- Participates in processing motor and sensory to permit movement, vision, and auditory functions
- Helps prevent the breakdown of muscle
- Necessary for a health digestive system
- Protects kidneys from harmful side effects of drugs
Glycine (receptors &agonist/antagonist)
Receptors
-Ionotropic only:
Agonists & Antagonist
DA (where is it synthesized & found)
-CNS: substantia nigra, midbrain (VTA), hypothalamus
-Main Projections: Striatum, Prefrontal Cortex,
Limbic Cortex, Nucleus Accumbens, Amygdala
-ANS: sympathetic neurons
DA (post-synaptic response & function)
excitatory & inhibitory
Functions: movements, initiative, working memory
-learning, motivation, HR, blood vessel
function, kidney function, sleep, mood,
attention, nausea/vomiting control, pain
processing
DA (receptors &agonist/antagonist)
Receptors:
-Metabotropic only
Agonist & Antagonists
Epinephrine (where is it synthesized & found)
- produced in adrenal glands & functions peripherally
- stored in the adrenal medulla
- when released it can affect heart, lungs, muscles, and blood vessels
Epinephrine (post-synaptic response & function)
excitatory
Function
- Classified as both NT and hormone
- Responds to strong emotions like such as fear or anger → causes epinephrine to be released → an increase in HR, BP, muscle strength, and sugar metabolism.
- The most notable function being those associated with the ‘fight or flight’ response to perceived danger.
Epinephrine (receptors &agonist/antagonist)
Receptors:
-Metabotropic only
Agonist & Antagonists
NE (where is it synthesized & found)
- Synthesized from dopamine in the adrenal gland
- Primarily found in cortex: locus ceruleus (pons), medulla and ANS: sympathetic neurons
NE (post-synaptic response & function)
excitatory
Function:
- Plays a vital role in active surveillance by increasing attention to sensory information
- Involved in sleep/wake cycle
- Sympathetic Nervous System: Essential for “fight or flight” reaction to stress
- Increases attention and focus,
- Involved in memory storage
- Involved in emotional control
NE (receptors &agonist/antagonist)
Receptors
-Metabotropic only
Agonists & Antagonists
5-HT (where is it synthesized & found)
- Produced in Raphe Nuclei of midline of brainstem
- Also produced by enterochromaffin cells in GI Tract
- Mainly stored in synaptic vesicles & platelets
5-HT (post-synaptic response & function)
inhibitory
Function:
- stabilizes mood
- controls bowel movements
- responsible for sleep
- can cause nausea
- help wound healing
- impacts bone health
5-HT (receptors &agonist/antagonist)
Receptors
- Ionotropic
- Metabotropic
Histamine (where is it synthesized & found)
- Secreted in hypothalamus within CNS and sored in hypothalamus and midbrain
- Most are found outside the nervous system because they are secreted by the hypothalamus
- Widespread projections to areas of the body within and outside of the nervous system
Histamine (receptors &agonist/antagonist)
Receptors
-Metabotropic only
Agonist & Antagonist
